79221693377 has 2 divisors, whose sum is σ = 79221693378. Its totient is φ = 79221693376.

The previous prime is 79221693367. The next prime is 79221693389. The reversal of 79221693377 is 77339612297.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70098387121 + 9123306256 = 264761^2 + 95516^2 .

It is a cyclic number.

It is not a de Polignac number, because 79221693377 - 2²⁸ = 78953257921 is a prime.

It is not a weakly prime, because it can be changed into another prime (79221693337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39610846688 + 39610846689.

It is an arithmetic number, because the mean of its divisors is an integer number (39610846689).

Almost surely, 2^79221693377 is an apocalyptic number.

It is an amenable number.

79221693377 is a deficient number, since it is larger than the sum of its proper divisors (1).

79221693377 is an equidigital number, since it uses as much as digits as its factorization.

79221693377 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6001128, while the sum is 56.

The spelling of 79221693377 in words is "seventy-nine billion, two hundred twenty-one million, six hundred ninety-three thousand, three hundred seventy-seven".