81912579268 has 96 divisors (see below), whose sum is σ = 158546626560. Its totient is φ = 36801198720.

The previous prime is 81912579257. The next prime is 81912579311. The reversal of 81912579268 is 86297521918.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 145492755 + ... + 145493317.

It is an arithmetic number, because the mean of its divisors is an integer number (1651527360).

Almost surely, 2^81912579268 is an apocalyptic number.

It is an amenable number.

81912579268 is a deficient number, since it is larger than the sum of its proper divisors (76634047292).

81912579268 is a wasteful number, since it uses less digits than its factorization.

81912579268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1097 (or 1095 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 58.

The spelling of 81912579268 in words is "eighty-one billion, nine hundred twelve million, five hundred seventy-nine thousand, two hundred sixty-eight".