87665 has 8 divisors (see below), whose sum is σ = 106920. Its totient is φ = 68992.

The previous prime is 87649. The next prime is 87671. The reversal of 87665 is 56678.

It can be written as a sum of positive squares in 4 ways, for example, as 18496 + 69169 = 136^2 + 263^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 87665 - 2⁴ = 87649 is a prime.

It is an Ulam number.

It is a nialpdrome in base 10.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 87665.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 347 + ... + 543.

It is an arithmetic number, because the mean of its divisors is an integer number (13365).

2⁸⁷⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

87665 is a deficient number, since it is larger than the sum of its proper divisors (19255).

87665 is a wasteful number, since it uses less digits than its factorization.

87665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291.

The product of its digits is 10080, while the sum is 32.

The square root of 87665 is about 296.0827587010. The cubic root of 87665 is about 44.4230881192.

The spelling of 87665 in words is "eighty-seven thousand, six hundred sixty-five".