About the Number 421 (four hundred twenty-one)

nBABs (number Basic Arithmetic Bits) turned six years of age on 22 April 2011 and whe nBAB count was 421 on that date.

   MathBabbler Number Analyst (MBNA) output:
   =========================================
   421 is a natural, whole, integer
   421 is odd
   421 proper divisors are: 1,
   421 is deficient (sum of divisors is 1)
   421 is unhappy
   421 is not a Harshad number
   421 is prime
   ...Twin prime with 419
   ...Pythagorean
   421 is a lucky number
   421 is the sum of 5 consecutive primes
   421 = 73 + 79 + 83 + 89 + 97
   421 in octal is 0645
   421 in hexadecimal is 0x1a5
   421 in binary is 110100101 (is odious)
   421 nearest square numbers: -21...20 (400...441 [21])
   sqrt(421) = 20.5183
   ln(421) = 6.04263
   log(421) = 2.62428
   421 reciprocal is .00237529691211401425178147268408
   421! is 4.96709e+923
   421 is 134.008 Pi years
   421 is 21 score and 1 year
   421 written as a Roman numeral is CDXXI
   421 = 211^2 - 210^2 and 211 + 210 = 421

4215 equals repdigit number 111.

4219 equals palindromic number 343.

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 24 April 2011