79905149721 has 12 divisors (see below), whose sum is σ = 115844451840. Its totient is φ = 53073529560.

The previous prime is 79905149683. The next prime is 79905149767. The reversal of 79905149721 is 12794150997.

It is not a de Polignac number, because 79905149721 - 2⁹ = 79905149209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (79905149221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16378281 + ... + 16383158.

It is an arithmetic number, because the mean of its divisors is an integer number (9653704320).

Almost surely, 2^79905149721 is an apocalyptic number.

It is an amenable number.

79905149721 is a deficient number, since it is larger than the sum of its proper divisors (35939302119).

79905149721 is a wasteful number, since it uses less digits than its factorization.

79905149721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32761716 (or 32761713 counting only the distinct ones).

The product of its (nonzero) digits is 1428840, while the sum is 54.

The spelling of 79905149721 in words is "seventy-nine billion, nine hundred five million, one hundred forty-nine thousand, seven hundred twenty-one".