78644894920 has 32 divisors (see below), whose sum is σ = 176961153600. Its totient is φ = 31456155328.

The previous prime is 78644894917. The next prime is 78644894959. The reversal of 78644894920 is 2949844687.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 817941 + ... + 909019.

It is an arithmetic number, because the mean of its divisors is an integer number (5530036050).

Almost surely, 2^78644894920 is an apocalyptic number.

It is an amenable number.

78644894920 is an abundant number, since it is smaller than the sum of its proper divisors (98316258680).

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

78644894920 is a wasteful number, since it uses less digits than its factorization.

78644894920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112677 (or 112673 counting only the distinct ones).

The product of its (nonzero) digits is 27869184, while the sum is 61.

The spelling of 78644894920 in words is "seventy-eight billion, six hundred forty-four million, eight hundred ninety-four thousand, nine hundred twenty".