87 (number)

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← 86 87 88 →
Cardinaleighty-seven
Ordinal87th
(eighty-seventh)
Factorization3 × 29
Divisors1, 3, 29, 87
Greek numeralΠΖ´
Roman numeralLXXXVII
Binary10101112
Ternary100203
Quaternary11134
Quinary3225
Senary2236
Octal1278
Duodecimal7312
Hexadecimal5716
Vigesimal4720
Base 362F36

87 (eighty-seven) is the natural number following 86 and preceding 88.

In mathematics[edit]

87 is:

  • the sum of the squares of the first four primes (87 = 22 + 32 + 52 + 72).
  • the sum of the sums of the divisors of the first 10 positive integers.[1]
  • the twenty-sixth distinct semiprime and the eighth of the form (3.q).
  • 5! - 4! - 3! - 2! - 1! = 87

In sports[edit]

In other fields[edit]

Eighty-seven is also:

See also[edit]


References[edit]

  1. ^ Sloane, N. J. A. (ed.). "Sequence A024916 (sum_{k=1..n} sigma(k) where sigma(n) = sum of divisors of n)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.