79771657220 has 12 divisors (see below), whose sum is σ = 167520480204. Its totient is φ = 31908662880.

The previous prime is 79771657211. The next prime is 79771657267. The reversal of 79771657220 is 2275617797.

It can be written as a sum of positive squares in 2 ways, for example, as 22409491204 + 57362166016 = 149698^2 + 239504^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1994291411 + ... + 1994291450.

It is an arithmetic number, because the mean of its divisors is an integer number (13960040017).

Almost surely, 2^79771657220 is an apocalyptic number.

It is an amenable number.

79771657220 is an abundant number, since it is smaller than the sum of its proper divisors (87748822984).

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

79771657220 is a wasteful number, since it uses less digits than its factorization.

79771657220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3988582870 (or 3988582868 counting only the distinct ones).

The product of its (nonzero) digits is 2593080, while the sum is 53.

The spelling of 79771657220 in words is "seventy-nine billion, seven hundred seventy-one million, six hundred fifty-seven thousand, two hundred twenty".