79638976820 has 24 divisors (see below), whose sum is σ = 180106609704. Its totient is φ = 29405160576.

The previous prime is 79638976811. The next prime is 79638976877. The reversal of 79638976820 is 2867983697.

It can be written as a sum of positive squares in 4 ways, for example, as 11982805156 + 67656171664 = 109466^2 + 260108^2 .

It is a Harshad number since it is a multiple of its sum of digits (65).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 153151619 + ... + 153152138.

It is an arithmetic number, because the mean of its divisors is an integer number (7504442071).

Almost surely, 2^79638976820 is an apocalyptic number.

It is an amenable number.

79638976820 is an abundant number, since it is smaller than the sum of its proper divisors (100467632884).

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

79638976820 is a wasteful number, since it uses less digits than its factorization.

79638976820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306303779 (or 306303777 counting only the distinct ones).

The product of its (nonzero) digits is 54867456, while the sum is 65.

The spelling of 79638976820 in words is "seventy-nine billion, six hundred thirty-eight million, nine hundred seventy-six thousand, eight hundred twenty".