About the Number 153 (one hundred fifty-three)

On 10 July 2009, Google morphed its logo to celebrate the birth of Nikola Telsa in 1856 (i.e. 153 years ago). Telsa was an electricity guru.

A couple of days earlier, MathBabbler was updating the nBAB for the number seven. While doing that he learned that seven was a narcissistic number. On 9 July 2009, MathBabbler posted a BAB announcing that the MBNA (MathBabbler Number Analyst) was modified to check for narcissistic numbers. MathBabbler used the number 153 to test the MBNA because 153 is a narcissistic number.

   MathBabbler Number Analyst (MBNA) output:
   =========================================
   153 is a natural, whole, integer
   153 is odd
   153 proper divisors are: 1,3,9,17,51,
   153 is deficient (sum of divisors is 81)
   153 is unhappy
   153 is a Harshad number
   153 is not prime
   153 has the prime factors: 3*3*17 (sum=23)
   153 sum of prime factors is: 23
   153 and 154 are a Ruth-Aaron pair (distinct prime factors)
   153 is narcissistic
   153 in octal is 0231
   153 in hexadecimal is 0x99
   153 in binary is 10011001 (is evil)
   153 nearest square numbers: -9...16 (144...169 [13])
   sqrt(153) = 12.3693
   ln(153) = 5.03044
   log(153) = 2.18469
   153 reciprocal is .00653594771241830065359477124183
   153! is 2.00634e+269
   153 is 48.7014 Pi years
   153 is 7 score and 13 years
   153 written as a Roman numeral is CLIII

[WolframAlpha.com] 153 has a representation as a sum of 2 squares: 3^2+12^2

[NUmberGossip.com] 153 is a vampire number.

On 10 June 2009, the MBNA did not check for vampire numbers.

OEIS.org::id:A020342, which states "Vampire numbers (definition 1): n has a nontrivial factorization using n's digits."

     126,   153,   688,  1206,  1255,  1260,  1395,  1435,  1503, 
    1530,  1827,  2187,  3159,  3784,  6880, 10251, 10255, 10426, 
   10521, 10525, 10575, 11259, 11439, 11844, 11848, 12006, 12060, 
   12384, 12505, 12546, 12550, 12595, 12600, 12762, 12768, 12798, 
   12843, 12955, 12964...

Let's check and see why 153 is a vampire number.

   the digits of 153 are 1, 5, 3 and 153 = 51 * 3 

   let's check 126...
   the digits of 126 are 1, 2, 6 and 126 = 21 * 6

   let's check 1827...
   the digits of 1827 are 1, 8, 2, 7 and 1827 = 21 * 87

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 10 July 2009