Mathematical Facts

The implicit curve equation (x²+y²-1)³-x²y³=0 produces the heart shape. 

The term Googol (10¹⁰⁰, ie, 10 followed by 100 zeros) was invented by a 9-year old boy Milton Sirotta. 

The Reuleaux Triangle is a shape of constant width other than a circle.  

           17 689 = 1332
         177 6889 = 13332 
       1777 68889 = 133332
     17777 688889 = 1333332
   177777 6888889 = 13333332
                 ...

The Seven Unsolved Millennium Prize Math Problems are:
1. P versus NP problem
2. Hodge Conjecture
3. Poincaré conjecture (solved in 2002)
4. Riemann Hypothesis
5. Yang-Mills Existence and Mass Gap
6. Navier-Stokes Existence and Smoothness
7. Birch and Swinnerton-Dyer Conjecture Submitted by: Ravi - Mississauga, Ontario, Canada

The Fibonacci sequence are numbers where each following number is the sum of the previous two:

0 1 1 2 3 5 8 13 21 34 55 89 ... 

A Palindrome Number is a number that reads the same backwards and forward, e.g. 13431. 

A dollar can be made into small change in 293 ways.

You can remember the value of Pi (3.1415926) by counting each word's letters in "May I have a large container of coffee?"

Multiplication and succession:

       1 × 8 + 1 = 9
      12 × 8 + 2 = 98
     123 × 8 + 3 = 987
            ...

and so on. 

 

142857 is a cyclic number, i.e., its digits are rotated around when multiplied by any number from 1 to 6. Like this:

     142857 × 1 =  142857 
     142857 × 5 = 7 14285
     142857 × 4 = 57 1428
     142857 × 6 = 857 142
     142857 × 2 = 2857 14
     142857 × 3 = 42857 1

1089 multiplied by 9 gives an exact reverse: 9801.  
  
  
    
  

From 0 to 1000, the letter "A" only appears in 1000 ("one thousand"). 

 

2 is called the "oddest" Even-Prime number. 2 is a unique Even-Prime because while all Evens are divisible by 2, any number apart from 2 that is divisible by 2, is not a Prime.

1 × 9 + 2 = 11 12 × 9 + 3 = 111 123 × 9 + 4 = 1111 ... ... and so on. 

40 when written "forty" is the only number with letters in alphabetical order, while "one" is the only one with letters in reverse order. 

1 googol = 10¹⁰⁰ 1 googolplex = 10^googol = 10¹⁰¹⁰⁰ (The "Google" website name was inspired by "Googol".)

111 111 111 × 111 111 111 = 12345678 9 87654321

Pi (3.14159...) is a number that cannot be written as a fraction. States

The opposite sides of a dice cube always add up to seven. 

21978 when multiplied by 4 is the same number with digits in reverse order:

     21978 × 4 = 87912

If you add up the numbers 1-100 consecutively (1+2+3+4+5...) the total is 5050.

The billionth digit of Pi is 9.

1 and 2 are the only numbers where they are the values of the numbers of factors they have.

2 and 5 are the only prime numbers that end in 2 or 5.

The largest known prime number (so far) is 12,978,189 digits long. Submitted by: Mathguy

The digits to the right of the Pi's (3.141...) decimal point can keep going forever, and there is no pattern to these digits at all.