Number 10

                                            Number 10

       1.      It is the base of our numerical system.

       2.      It is the fifth even number. The other four preceding 10 are 2, 4, 6 and 8.

       3.      It is the fourth triangular number. The first three are 1, 3 and 6.

      4.      It is the sum of square of two consecutive odd numbers.                

                                                  10 = 1² + 3²

      5.      October 10, 2010 is written as 10/10/2010. The occurrence of such number is special because the first tow number added together equals the first two digits of the year. Here 10 + 10 = 20 is the first two digit of the year 2010. Such date occurs in every 201 years. The next such combination will occur on 11/11/2211.

        6.      It is the fifth composite number. The first four are 4, 6, 8 and 9.

       7.      Divisibility by 10:- If a number ends with zero it is exactly divisible by 10.         

                          Example:- 100, 560540

       8.      Roman numerals for ten is X. It represents two crossed hands.

     9.      Take any triangle and divide each side into three equal parts. Draw lines from these to the opposite corners. A new shape will appear in the middle of the triangle whose area is 1/10^th of the area of whole triangle. This is known as Marion Walter Theorem. This theorem state - the area of the central hexagonal region determined by trisection of each side of a triangle and connecting the corresponding points with the opposite vertex is given by 1/10 the area of the original triangle.

10.  The strength of earth quake is measured on the Richter scale. Each point on the Richter scale represents a tenfold increase in energy. The Richter scale is a logarithmic scale used to express the total amount of energy released by an earthquake. Its values typically fall between 0 and 9, with each increase of 1 representing a 10 fold increase in energy.      

Value	1	2	3	4	5	6	7	8	9	10
Potential Hazard	Extra-ordinary	Outstanding	Far reaching	High	Note worthy	Intermediate	Moderate	Minim	Low	insignificant

     11.  It is the sum of first three primes.                                                                                                

       10 = 2 + 3 + 5

    12.  It is the sum of three consecutive (3^rd, 4^th and 5^th) Fibonacci numbers.

   13.  The only known solution to                                                                                                            

             n! = a! b!                                                                 is  10! = 6! X 7!

There are only 11 powers of 10 that are products of two integers without any zero. These are--                                                                                                                                           

           10⁰ = 1                         10¹ = 2 x 5                            10² = 4 x 25                             

            10³ = 8 x 125               10⁴ = 16 x 625                         10⁵ = 32 x 3125                                                 10⁶ = 64 x 15625         10⁷ = 128 x 78125                   10⁹ = 512 x 1953125             

14. This beautiful formula according to Ramanujan came into his dream

15. 10! seconds = 6 weeks

16. Ten is the smallest semi-prime that is the sum of all the distinct prime numbers from its lower factor through its higher factor. 
10 = 2 x 5 
10 = 2 + 3 + 5

17. It is the sum of first four factorials
0! + 1 ! + 2 ! + 3 ! = 10 

18. It is a tetrahedral number or triangular pyramidal  number.
1 4,  10, 20 

      Read more on Mathematical Number in my book THE POWER OF MATHEMATICAL NUMBER available on website 

Rajesh Thakur

rkthakur1974@gmail.com