87921636 has 24 divisors (see below), whose sum is σ = 223800864. Its totient is φ = 26642880.

The previous prime is 87921629. The next prime is 87921641. The reversal of 87921636 is 63612978.

It is a happy number.

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, 332905 + ... + 333168.

It is an arithmetic number, because the mean of its divisors is an integer number (9325036).

Almost surely, 2^87921636 is an apocalyptic number.

It is an amenable number.

87921636 is an abundant number, since it is smaller than the sum of its proper divisors (135879228).

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

87921636 is a wasteful number, since it uses less digits than its factorization.

87921636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666091 (or 666089 counting only the distinct ones).

The product of its digits is 108864, while the sum is 42.

The square root of 87921636 is about 9376.6537741350. The cubic root of 87921636 is about 444.6639486188.

The spelling of 87921636 in words is "eighty-seven million, nine hundred twenty-one thousand, six hundred thirty-six".