78661920072 has 32 divisors (see below), whose sum is σ = 196856143200. Its totient is φ = 26193794304.

The previous prime is 78661920059. The next prime is 78661920089. The reversal of 78661920072 is 27002916687.

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, 1653922 + ... + 1700817.

It is an arithmetic number, because the mean of its divisors is an integer number (6151754475).

Almost surely, 2^78661920072 is an apocalyptic number.

It is an amenable number.

78661920072 is an abundant number, since it is smaller than the sum of its proper divisors (118194223128).

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

78661920072 is a wasteful number, since it uses less digits than its factorization.

78661920072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3355725 (or 3355721 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 48.

The spelling of 78661920072 in words is "seventy-eight billion, six hundred sixty-one million, nine hundred twenty thousand, seventy-two".