87721164 has 24 divisors (see below), whose sum is σ = 227425520. Its totient is φ = 29240352.

The previous prime is 87721133. The next prime is 87721189. The reversal of 87721164 is 46112778.

It is a super-2 number, since 2×87721164² = 15390005227029792, 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 7 ways as a sum of consecutive naturals, for example, 406009 + ... + 406224.

Almost surely, 2^87721164 is an apocalyptic number.

It is an amenable number.

87721164 is an abundant number, since it is smaller than the sum of its proper divisors (139704356).

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

87721164 is a wasteful number, since it uses less digits than its factorization.

87721164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812246 (or 812238 counting only the distinct ones).

The product of its digits is 18816, while the sum is 36.

The square root of 87721164 is about 9365.9577193152. The cubic root of 87721164 is about 444.3257288390.

The spelling of 87721164 in words is "eighty-seven million, seven hundred twenty-one thousand, one hundred sixty-four".