81976164 has 24 divisors (see below), whose sum is σ = 196448448. Its totient is φ = 26586720.

The previous prime is 81976129. The next prime is 81976187. The reversal of 81976164 is 46167918.

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, 91872 + ... + 92759.

It is an arithmetic number, because the mean of its divisors is an integer number (8185352).

Almost surely, 2^81976164 is an apocalyptic number.

It is an amenable number.

81976164 is an abundant number, since it is smaller than the sum of its proper divisors (114472284).

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

81976164 is a wasteful number, since it uses less digits than its factorization.

81976164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184675 (or 184673 counting only the distinct ones).

The product of its digits is 72576, while the sum is 42.

The square root of 81976164 is about 9054.0689195521. The cubic root of 81976164 is about 434.4060489443.

The spelling of 81976164 in words is "eighty-one million, nine hundred seventy-six thousand, one hundred sixty-four".