79638976821 has 16 divisors (see below), whose sum is σ = 108238897728. Its totient is φ = 52075680000.

The previous prime is 79638976811. The next prime is 79638976877. The reversal of 79638976821 is 12867983697.

It is not a de Polignac number, because 79638976821 - 2⁶ = 79638976757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79638976801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1195780 + ... + 1260621.

It is an arithmetic number, because the mean of its divisors is an integer number (6764931108).

Almost surely, 2^79638976821 is an apocalyptic number.

It is an amenable number.

79638976821 is a deficient number, since it is larger than the sum of its proper divisors (28599920907).

79638976821 is a wasteful number, since it uses less digits than its factorization.

79638976821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2456612.

The product of its digits is 54867456, while the sum is 66.

The spelling of 79638976821 in words is "seventy-nine billion, six hundred thirty-eight million, nine hundred seventy-six thousand, eight hundred twenty-one".