87865 has 4 divisors (see below), whose sum is σ = 105444. Its totient is φ = 70288.

The previous prime is 87853. The next prime is 87869. The reversal of 87865 is 56878.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56878 = 2 ⋅28439.

It can be written as a sum of positive squares in 2 ways, for example, as 46656 + 41209 = 216^2 + 203^2 .

It is a cyclic number.

It is not a de Polignac number, because 87865 - 2⁵ = 87833 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 87865.

It is not an unprimeable number, because it can be changed into a prime (87869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8782 + ... + 8791.

It is an arithmetic number, because the mean of its divisors is an integer number (26361).

2⁸⁷⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

87865 is a deficient number, since it is larger than the sum of its proper divisors (17579).

87865 is a wasteful number, since it uses less digits than its factorization.

87865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17578.

The product of its digits is 13440, while the sum is 34.

The square root of 87865 is about 296.4203096955. The cubic root of 87865 is about 44.4568449194.

The spelling of 87865 in words is "eighty-seven thousand, eight hundred sixty-five".