Hundred doesn’t mean hundred: The word “hundred” is actually derived from the Old Norse word “hundrath” which actually means 120 not 100. More specifically “hundrath” in Old Norse, means “long hundred” which is equal to 120, due to duodecimal system.

There is only one even prime number: A prime number is a whole number greater than 1 whose only factors are 1 and itself. A factor is a whole number that can be divided evenly into another number. The number 2 is also the smallest and first prime number (since every other even number is divisible by two).

Zero is the only number that can’t be represented in roman numerals: The idea of 0 as a number was invented throughout the world at different times in history. Despite this scattered adoption, it’s generally accepted that the Indian astronomer and mathematician Brahamagupta brought up the concept of zero for the first time, around 600 A.D. Beside this, Brahamagupta contributed a lot to mathematics and astronomy and is known for explaining how to find the cube and cube root of an integer and also gave rules facilitating the computation of squares and square roots.

The square root of 2 if called Pythagoras Constant: Surely, you remember the Pythagorean Theorem from you secondary classes, but have you ever heard of Pythagoras Constant? Well here’s the lowdown. The square root of 2 (1.41) is known as Pythagoras constant. It’s also the very first irrational number ever to be discovered.

Zero is an even number: Mathematically, an even number is one that can be divided by two and still create a whole number. Zero meets the criteria for this because if you halve zero you get zero. But if you’re confused, you are not alone. Research from 1990’s out of Cambridge University, actually revealed that people are 10 percent slower at deciding whether zero is even or not than they are if, say two is.

There is only one number spelled with the same number of letters as itself: You probably never thought this before, but there is only one number spelled with the same number of letters as itself. It’s 4, and the number 4 on a calculator is made up of four light bars.

Six is the Smallest Perfect number: In number theory, a perfect number is a positive integer that is equal to the sum of its positive divisors. By this rule, 6 is the smallest perfect number. - - - >> 1+2+3=6.

The number Pi is irrational: The number Pi – also known as the ratio of the circumference to the diameter of the circle – is irrational. This is because Pi cannot be written as a fraction. Also: Pi, when written as a decimal, never repeats and never ends. And there is a designated Pi Day (March 14th or 3/14).

2 & 5 are the only prime numbers that end with 2 & 5: Other numbers ending with 2 or 5 are either divisible by 2 or 5. A prime number is a natural number greater than 1 that cannot be created by multiplying two smaller natural numbers. So, to put that in non – math talk, prime numbers are numbers greater than 1 that can be formed by multiplying 1 by itself. A natural number greater than one that is not prime is called a composite number.

9 is considered as a magic number: Have you ever heard that the number 9 is considered to be a “magic” number? Here is why: if you multiply a number by 9 and add all the digits of the new number together, the sum will always add up to 9. It is truly magical. Try it out. Every single combination will always lead you back to 9.

One (1) is not a prime number: Often, the number 1 is confused as a prime number. But that’s not the case – one does not fulfill the requirements to be prime (being divisible by both 1 and itself). Divide 1 by 1 and you get 1. Nothing has been divided.

7 is the most popular “Favorite Number”: If you walked up to someone on the street and asked them what their favorite number is – of all whole numbers between 1 and 100 – there’s almost 10% chance they will say “7”.

The most popular two digit number is 13: You’d think unlucky number 13 would be one that most people want to stay away from. But in Alex Bello’s research, it turned out to be the most popular two digit number (selected by 5% of all respondents) and sixth – most popular number overall (following – 7,3,8,4 and 5 in top five spots – that’s right the number 5 is also fifth most popular number.

7 is arithmetically unique: The number 7 may be so popular because it is arithmetically unique. Alex Bello’s explanation: “Of the first 10 numbers, seven is the most prime. You can’t multiply or divide it within the group. It feels unique”. For example you could multiply 4 by 2 to get 8 or divide 10 by 2 to get 5 but there’s nothing you can do with 7.

Six weeks = 10! Seconds: That is 10x9x8x7x6x5x4x3x2x1 = 3628800 seconds = 60480 minutes = 1008 hours = 42 days = 6 weeks.

There is not Enough Room in the world to write out a Googolplex: A Googol means 1 followed by 100 zeros. A Googolplex is 1 followed by a googol zeros. If it’s hard to imagine how long that number would look. There is good reason for that: to write it out would create a number that’s so huge, if you wrote it out and printed it in a volume series of books, it would weigh more than entire planet.

(6x9)+(6+9) = 69 : Don’t laugh. Just type that into your calculator and you’ll see it’s true.

40 below is the only temperature that is the same in both Fahrenheit and Celsius.

111,111,111 x 111,111,111 = 12345678987654321: Though good luck finding a calculator that can factor equations in millions.