79640821216858 has 24 divisors (see below), whose sum is σ = 131465133162720. Its totient is φ = 36157226140200.

The previous prime is 79640821216849. The next prime is 79640821216883. The reversal of 79640821216858 is 85861212804697.

It is a hoax number, since the sum of its digits (67) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 79640821216793 and 79640821216802.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 195919908 + ... + 196325983.

It is an arithmetic number, because the mean of its divisors is an integer number (5477713881780).

Almost surely, 2^{79640821216858} is an apocalyptic number.

79640821216858 is a deficient number, since it is larger than the sum of its proper divisors (51824311945862).

79640821216858 is a wasteful number, since it uses less digits than its factorization.

79640821216858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392246754 (or 392246743 counting only the distinct ones).

The product of its (nonzero) digits is 92897280, while the sum is 67.

The spelling of 79640821216858 in words is "seventy-nine trillion, six hundred forty billion, eight hundred twenty-one million, two hundred sixteen thousand, eight hundred fifty-eight".