79991201321 has 2 divisors, whose sum is σ = 79991201322. Its totient is φ = 79991201320.

The previous prime is 79991201317. The next prime is 79991201363. The reversal of 79991201321 is 12310219997.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71256429721 + 8734771600 = 266939^2 + 93460^2 .

It is a cyclic number.

It is not a de Polignac number, because 79991201321 - 2² = 79991201317 is a prime.

It is not a weakly prime, because it can be changed into another prime (79991201621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39995600660 + 39995600661.

It is an arithmetic number, because the mean of its divisors is an integer number (39995600661).

Almost surely, 2^79991201321 is an apocalyptic number.

It is an amenable number.

79991201321 is a deficient number, since it is larger than the sum of its proper divisors (1).

79991201321 is an equidigital number, since it uses as much as digits as its factorization.

79991201321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 61236, while the sum is 44.

The spelling of 79991201321 in words is "seventy-nine billion, nine hundred ninety-one million, two hundred one thousand, three hundred twenty-one".