## Number of the Week Archive (2015)

### Number of the Week (14 December 2015)

This week’s number is 37.

The factors of 37 are 1 and 37

37 in Roman numerals is expressed as XXXVII

37 is 100101 in binary.

37 is the 12th Prime number

37 and 38 are the first pair of consecutive positive integers that are not divisible by any of their digits.

37 is the normal human body temperature in degrees Celsius.

William Shakespeare is thought to have written 37 plays (counting Henry IV as three parts).

In gambling, there are 37 numbers on a roulette wheel (0 – 36).

There are 10 international dialing codes that begin with the digits 37.

37 is the number people choose most often when asked to give a number between 1 and 100.

### Number of the Week (30 November 2015)

This week’s number is 11.

The factors of 11 are 1 and 11.

11 in Roman numerals is expressed as XI.

11 is 1011 in binary.

11 is the 5th Prime number.

An 11-sided polygon is called a hendecagon or undecagon.

Apollo 11 was the first manned spacecraft to land on the Moon.

There are 11 players in soccer and field hockey teams.

In American football there are 11 players on the field at any on time.

If a number is divisible by 11, reversing its digits will result in another multiple of 11.

World War One ended on with an Armistice in November, 1918. It went into effect at 11am on the 11th day of the 11th month.

The maple leaf on the flag of Canada has 11 points.

### Number of the Week (16 November 2015)

This week’s number is 53.

The factors of 53 are 1 and 53.

53 in Roman numerals is expressed as LIII

53 is 110101 in binary.

53 is the 16th Prime number.

53 is the atomic number of iodine.

53 is the international direct dial number for phone calls to Cuba.

53 was the racing number of Herbie, the VW Beetle from the 1969 movie, The Love Bug.

53 was the record number of field goals scored by Michael Jordan, in a three-game series in the NBA Basket ball play-offs, in 1992.

### Number of the Week (2 November 2015)

This week’s number is 99.

The factors of 99 are 1, 3, 9, 11, 33, 99.

99 in Roman numerals is expressed as XCIX

The prime factors of 99 are 3 x 3 x 11

99 is 1100011 in binary.

99 is the sum of the cubes of three consecutive whole numbers 23 + 33 + 43

99 is a palindromic number.

99 is the atomic number of Einsteinium. It was discovered in 1952 in the debris of the first H-bomb explosion and named after Albert Einstein.

The earliest known reference to a 99-flake ice-cream with a chocolate flake was in 1935. One idea links it to a shop in Scotland at 99 Portobello High St which added chocolate flakes to its ice-creams.

“If you wish to live to the age of 99, please walk. 100 steps after each meal,” (Chinese proverb).

### Number of the Week (19 October 2015)

This week’s number is 14.

The factors of 14 are 1, 2, 7, 14.

14 in Roman numerals is expressed as XIV

The prime factors of 14 are 2 x 7

14 is 1110 in binary.

14 is the sum of the first three square numbers making it a square pyramidal number.

There are 14 pounds in a stone. (British weight measurements before metrics)

The atomic number of Silicon is 14.

14 is the number of days in a fortnight.

The Top 14 is the highest-level rugby competition in France.

14 – the shirt number worn by Johan Cruyff, the Dutch footballer. No longer used by his former club Ajax.

There are 14 lines in a sonnet.

February 14 – St Valentine’s Day

### Number of the Week (21 September 2015)

This week’s number is 95.

The factors of 95 are 1, 5, 19, 95.

95 in Roman numerals is expressed as XCV

The prime factors of 95 are 5 x 19

95 is 1011111 in binary.

In statistics a 95 % confidence interval is considered satisfactory for most purposes.

Hit 95 FM- A popular Indian radio station.

The atomic number of Americium is 95.

United States Interstate 95, a freeway that runs from Florida to Maine.

Windows 95 A popular computer operating system.

95 – a good mark and a good age!

### Number of the Week (14 September 2015)

This week’s number is 25.

The factors of 25 are 1, 5, 25.

25 in Roman numerals is expressed as XXV

The prime factors of 25 are 5 x 5 or 52

25 is 11001 in binary.

25 is the smallest square that is also the sum of two non-zero squares (25 = 32 + 42)

25 is a square number 52 = 25

25 years of marriage is marked by a SILVER wedding anniversary.

The atomic number of Manganese is 25.

The M 25 is a motorway around London.

United States Interstate 25, a freeway that runs from New Mexico to Wyoming.

### Number of the Week (7 September 2015)

This week’s number is 57.

The factors of 57 are 1, 3, 19 and 57.

57 in Roman numerals is expressed as LVII.

The prime factors of 57 are 3 x 19.

57 is 111001 in binary.

57 is the number of varieties of foods claimed to be produced by the H.J. Heinz Company.

The code of international dialling calls to Columbia is 57

The atomic number of Lanthanum is 57.

Interstate 57 is a freeway in the USA that runs from Missouri to Chicago.

### Number of the Week (31 August 2015)

This week’s number is 26.

The factors of 26 are 1, 2, 13, and 26.

26 in Roman numerals is expressed as XXVI

The prime factors of 26 are 2 x 13.

26 is 11010 in binary.

The atomic number of Iron is 26.

A rhombicuboctahedron has 26 faces.

When 27 small cubes are made into a larger 3x3x3 cube, 26 of them can be seen on the outside of the larger cube.

There are 26 miles, rounded, in a marathon running race.

26 is the "joke throw" in the game of darts, where a player throws 20, 5 and 1 when aiming for 20 (or treble 20). In professional darts, throwing 26 usually results in sneers or laughter from the audience.

26 is the number of bones in the normal human foot and ankle.

26 is the number of letters in the English alphabet.

There are 26 red cards and 26 black cards in a normal deck of cards.

26 is the only number that is 1 more than a square number (25 = 52) AND 1 less than a cube (27 = 33)

### Number of the Week (24 August 2015)

This week’s number is 19.

19 is the 8th prime number.

19 in Roman numerals is expressed as XIX.

19 is 10011 in binary.

19 is a centred triangle number.

The atomic number of Potassium is 19.

The game of GO, is usually played on a grid of 19 X 19.

19 (or 18) is often the minimum age for buying alcohol and tobacco in many places around the world.

### Number of the Week (17 August 2015)

This week’s number is 77.

77 is the sum of the first eight prime numbers.
i.e. 2 + 3 + 5 + 7 + 11 + 13 + 17 + 19

77 is the sum of the squares of three consecutive whole numbers.
i.e. 42 + 52 + 62

The prime factors of 77 are 7 and 11.

77 in Roman numerals is expressed as LXXVII.

77 is 1001101 in binary.

77 Sunset strip was a popular TV programme in the 1950’s-1960’s

The atomic number of iridium is 77.

77 is the boiling point of nitrogen (in degrees Kelvin), that is equal to –195.79oC.

77 is the only whole number under 100 which when spoken has 5 syllables.

### Number of the Week (10 August 2015)

This week’s number is 33.

33 is the smallest sum of two different positive numbers each of which raised to the fifth power: 15 + 25

33 is the largest positive integer that cannot be expressed as the sum of different triangle numbers.

The prime factors of 33 are 3 and 11.

In Roman Numerals the number 33 can be written as XXXIII.

33 is 100001 in binary.

The atomic number of arsenic is 33.

A normal human spine has 33 vertebrae when the bones that form the coccyx are counted individually.

In the Bible, Jesus’s age when he was crucified was 33 (Hence 33AD)

Islamic prayer beads are generally arranged in sets of 33.

In reference to vinyl gramophone records, 33 represents a type of record (known as an LP or long-playing record) with a speed of 33 1/3 revolutions per minute.

In the English Premier league, the former Chelsea goal-keeper Petr Cech selected the squad number 33 on signing for Arsenal FC in June 2015. He cited that it represented his age 33, his 333 Premier League games and that he wanted to be the spine (with 33 vertebrae) of the team.

### Number of the Week (3 August 2015)

This week’s number is 8.

8 is a composite number. It is the first number that is neither prime nor semi-prime.

8 is a power of 2 i.e. 23.

A number is divisible by 8 if the number formed by the last three digits are divisible by 8.

The number 8 is an even number.

The factors of 8 are 1, 2, 4 and 8 – so 8 is divisible by 4 numbers.

8 is a Fibonacci number (3 + 5).

A polygon with 8 sides is called an octagon.

A polyhedron with 8 faces is called an octahedron. Each face is an equilateral triangle.

A cube has 8 vertices.

A octahedron has faces as 6 congruent squares and 8 congruent equilateral triangles.

In Roman Numerals the number 8 can be written as VIII.

8 is the atomic number of oxygen.

All spiders have 8 legs.

A byte is bits.

There are furlongs in a mile.

### Number of the Week (20 July 2015)

This week’s number is 91.

91 is a triangle number.

91 is the 27th distinct semiprime.

The code of international direct dial phone calls to India is 91.

The number 91 is an odd number.

The factors of 91 are 1, 7, 13, and 91 – so 91 is divisible by 4 numbers.

The only prime factors of 91 are 7 and 13.

91% as a fraction is 91/100 or 0.91 as a decimal.

In the binary number system 91 can be written as 1011011.

In Roman Numerals the number 91 can be written as XCI.

If you travelled a distance of 91 miles then this would be equivalent to about 146 kilometers.

Also a length of 91 feet is equivalent to 28 meters.

A weight of 91 pounds is equivalent to 41.3 kilograms.

A temperature of 91 degree Celsius is about 196 degree Fahrenheit.

91 is the atomic number of protactinium, an actinide.

### Number of the Week (29 June 2015)

This week’s number is 46.

46 is the number of human chromosomes.

46 is the 16th semiprime.

In geometry, the name of a 46 sided polygon is called a tetracontakaihexagon.

The number 46 is an even number - the 23rd even number to be precise.

The factors of 46 are 1, 2, 23 and 46 – so 46 is divisible by 4 numbers.

The only prime factors of 46 are 2 and 23

46% as a fraction is 23/50 or 0.46 as a decimal.

In the binary number system 46 can be written as 101110.

In Roman Numerals the number 46 can be written as XLVI.

If you travelled a distance of 46 miles then this would be equivalent to 74 kilometers.

Also a length of 46 feet is equivalent to 14.0 meters.

A weight of 46 pounds is equivalent to 20.9 kilograms.

A temperature of 46 degree Celsius is about 115 degree Fahrenheit.

### Number of the Week (22 June 2015)

This week’s number is 89.

89 is the 24th Prime Number.

89 is a Fibonacci number and therefore a Fibonacci Prime.

89 is the 10th Mersenne Prime.

89 is part of the Pythagorean Triple (39, 80, 89) because 392 + 802 = 892.

89 is an atomic number of the element actinium.

### Number of the Week (15 June 2015)

This week’s number is 49.

49 is a square number. 49 = 72

49 is the first square where the digits are squares (4 and 9).

Arsenal Football Club, in the English Premier League, had an unbeaten run of 49 games between May 2003 through to October 2004 when they lost to Manchester United. This remains a national record in English football.

49 is the atomic number of the element indium.

The sum of the digits of the square of 49 (2401) is the square root of 49.

49 is trimorphic, that is, its cube ends in the same digits i.e. 493 = 117649

### Number of the Week (8 June 2015)

This week’s number is 35.

35 is the sum of the first 5 triangle numbers. i.e. 1 + 3 + 6 + 10 + 15 = 35.

35 is a tetrahedral number.

35 is the number of ways 3 objects can be selected from 7 objects (a combination)

35 is a semi-prime (a product of two prime numbers 5 x 7)

There are 35 hexominoes (polyominoes made from 6 squares)