87215904 has 36 divisors (see below), whose sum is σ = 248021046. Its totient is φ = 29071872.

The previous prime is 87215837. The next prime is 87215923. The reversal of 87215904 is 40951278.

It can be written as a sum of positive squares in only one way, i.e., 86490000 + 725904 = 9300^2 + 852^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×87215904² = 15213227821074432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 151129 + ... + 151704.

Almost surely, 2^87215904 is an apocalyptic number.

It is an amenable number.

87215904 is an abundant number, since it is smaller than the sum of its proper divisors (160805142).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

87215904 is a wasteful number, since it uses less digits than its factorization.

87215904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302849 (or 302838 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 87215904 is about 9338.9455507568. The cubic root of 87215904 is about 443.4710037828.

The spelling of 87215904 in words is "eighty-seven million, two hundred fifteen thousand, nine hundred four".