About the Number 281 (two hundred eighty-one)

While creating a nBAB for the number 251, MathBabbler noticed it is a Truman-Gerald Pair with the number 281. Note: A Truman-Gerald Pair are two prime numbers that differ by 30.

   MathBabbler Number Analyst (MBNA) output:
   =========================================
   281 is a natural, whole, integer
   281 is odd
   281 proper divisors are: 1,
   281 is deficient (sum of divisors is 1)
   281 is unhappy
   281 is a Squarefree Number
   281 is not a Harshad number
   281 is prime
   ...Cousin prime with 277
   ...Sophie Germain prime with 563
   ...Twin prime with 283
   ...Truman Gerald prime with 311
   ...Truman Gerald prime with 251
   ...Pythagorean
   ...Eisenstein
   ...prime triplet {277, 281, 283}
   281 is the sum of 14 consecutive primes
   281 = 2 + 3 + 5 + 7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37 + 41 + 43
   281 in octal is 0431
   281 in hexadecimal is 0x119
   281 in binary is 100011001 (is evil)
   281 nearest square numbers: -25...8 (256...289 [17])
   sqrt(281) = 16.7631
   ln(281) = 5.63835
   log(281) = 2.44871
   281 reciprocal is .00355871886120996441281138790035
   281! is 4.71301e+567
   281 is 89.4451 Pi years
   281 is 14 score and 1 year
   281 written as a Roman numeral is CCLXXXI
   281 = 141^2 - 140^2 and 141 + 140 = 281

log6(281) = 3.14683, which when truncated to two decimal digits equals Pi rounded to the nearest hundredth.


Creator: Gerald Thurman [gthurman@gmail.com]
Created: 27 June 2012

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