81612750788 has 12 divisors (see below), whose sum is σ = 143849813520. Its totient is φ = 40512804072.

The previous prime is 81612750683. The next prime is 81612750809. The reversal of 81612750788 is 88705721618.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 73392206 + ... + 73393317.

It is an arithmetic number, because the mean of its divisors is an integer number (11987484460).

Almost surely, 2^81612750788 is an apocalyptic number.

It is an amenable number.

81612750788 is a deficient number, since it is larger than the sum of its proper divisors (62237062732).

81612750788 is a wasteful number, since it uses less digits than its factorization.

81612750788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146785666 (or 146785664 counting only the distinct ones).

The product of its (nonzero) digits is 1505280, while the sum is 53.

The spelling of 81612750788 in words is "eighty-one billion, six hundred twelve million, seven hundred fifty thousand, seven hundred eighty-eight".