About the Number 87 (eighty-seven)

MathBabbler came across a BARS that was created for a road sign in which no math was found. One week earlier, a BARS was chosen for BOTW that had a sign for which no math was initially found. In both cases the number 87 was the source of the problem.

   MathBabbler Number Analyst (MBNA) output:
   =========================================
   87 is a natural, whole, integer
   87 is odd
   87 proper divisors are: 1,3,29,
   87 is deficient (sum of divisors is 33)
   87 is unhappy
   87 is not a Harshad number
   87 is not prime
   87 is undulating
   87 has the prime factors: 3*29
   87 in octal is 0127
   87 in hexadecimal is 0x57
   87 in binary is 1010111 (is odious)
   87 nearest square numbers: -6...13 (81 [9] ...100 [10])
   sqrt(87) = 9.32738
   ln(87) = 4.46591
   log(87) = 1.93952
   87 reciprocal is .01149425287356321839080459770114
   87! is 2.10776e+132
   87 is 27.693 Pi years
   87 is 4 score and 7 years

87 in Roman numeral is LXXXVII.

The Wikipedia said: 87 is the sum of the squares of the first four primes.

   2^2 + 3^2 + 5^2 + 7^2 = 4 + 9 + 25 + 49 = 87

The Wikipedia also said: 87 is the sum of the sum of divisors of the first ten integers.

    1:  1 
    2:  1 + 2 = 3
    3:  1 + 3 = 4
    4:  1 + 2 + 4 = 7
    5:  1 + 5 = 6
    6:  1 + 2 + 3 + 6 = 12
    7:  1 + 7 = 8
    8:  1 + 2 + 4 + 8 = 15
    9:  1 + 3 + 9 = 13
   10:  1 + 2 + 5 + 10 = 18

   1 + 3 + 4 + 7 + 6 + 12 + 8 + 15 + 13 + 18 = 87

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 17 October 2008

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