79791021 has 8 divisors (see below), whose sum is σ = 118208960. Its totient is φ = 53193996.

The previous prime is 79790999. The next prime is 79791031. The reversal of 79791021 is 12019797.

It is not a de Polignac number, because 79791021 - 2⁹ = 79790509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79791031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1477585 + ... + 1477638.

It is an arithmetic number, because the mean of its divisors is an integer number (14776120).

Almost surely, 2^79791021 is an apocalyptic number.

It is an amenable number.

79791021 is a deficient number, since it is larger than the sum of its proper divisors (38417939).

79791021 is a wasteful number, since it uses less digits than its factorization.

79791021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2955232 (or 2955226 counting only the distinct ones).

The product of its (nonzero) digits is 7938, while the sum is 36.

The square root of 79791021 is about 8932.5819895482. The cubic root of 79791021 is about 430.5114178278.

The spelling of 79791021 in words is "seventy-nine million, seven hundred ninety-one thousand, twenty-one".