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# 87 (number)

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### 87 (number)

 ← 86 87 88 →
Cardinal eighty-seven
Ordinal 87th
(eighty-seventh)
Factorization 3 × 29
Divisors 1, 3, 29, 87
Roman numeral LXXXVII
Binary 10101112
Ternary 100203
Quaternary 11134
Quinary 3225
Senary 2236
Octal 1278
Duodecimal 7312
Vigesimal 4720
Base 36 2F36

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

## In mathematics

87 is the twenty-sixth distinct semiprime and the eighth of the form (3.q). The aliquot sum of 87 is 33 within the aliquot sequence (87,33,15,9,4,3,1,0) 86 being the eighteenth composite number in the 3-aliquot tree.

87 is the sum of the squares of the first four primes. It is also the sum of the sum of divisors of the first ten integers.

## In other fields

Eighty-seven is also:

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