79721598990 has 48 divisors (see below), whose sum is σ = 210306905424. Its totient is φ = 19326447360.

The previous prime is 79721598961. The next prime is 79721598997. The reversal of 79721598990 is 9989512797.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79721598997) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10977307 + ... + 10984566.

It is an arithmetic number, because the mean of its divisors is an integer number (4381393863).

Almost surely, 2^79721598990 is an apocalyptic number.

79721598990 is an abundant number, since it is smaller than the sum of its proper divisors (130585306434).

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

79721598990 is a wasteful number, since it uses less digits than its factorization.

79721598990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21961905 (or 21961894 counting only the distinct ones).

The product of its (nonzero) digits is 25719120, while the sum is 66.

The spelling of 79721598990 in words is "seventy-nine billion, seven hundred twenty-one million, five hundred ninety-eight thousand, nine hundred ninety".