79815720 has 32 divisors (see below), whose sum is σ = 239447520. Its totient is φ = 21284160.

The previous prime is 79815709. The next prime is 79815761. The reversal of 79815720 is 2751897.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 332446 + ... + 332685.

It is an arithmetic number, because the mean of its divisors is an integer number (7482735).

Almost surely, 2^79815720 is an apocalyptic number.

It is an amenable number.

79815720 is an abundant number, since it is smaller than the sum of its proper divisors (159631800).

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

79815720 is a wasteful number, since it uses less digits than its factorization.

79815720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 665145 (or 665141 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 39.

The square root of 79815720 is about 8933.9644055705. The cubic root of 79815720 is about 430.5558342897. Note that the first 3 decimals are identical.

The spelling of 79815720 in words is "seventy-nine million, eight hundred fifteen thousand, seven hundred twenty".