79821390 has 32 divisors (see below), whose sum is σ = 208987776. Its totient is φ = 19350560.

The previous prime is 79821353. The next prime is 79821407. The reversal of 79821390 is 9312897.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120612 + ... + 121271.

It is an arithmetic number, because the mean of its divisors is an integer number (6530868).

Almost surely, 2^79821390 is an apocalyptic number.

79821390 is an abundant number, since it is smaller than the sum of its proper divisors (129166386).

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

79821390 is a wasteful number, since it uses less digits than its factorization.

79821390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241904.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 79821390 is about 8934.2817282644. The cubic root of 79821390 is about 430.5660294149.

The spelling of 79821390 in words is "seventy-nine million, eight hundred twenty-one thousand, three hundred ninety".