79719698657 has 2 divisors, whose sum is σ = 79719698658. Its totient is φ = 79719698656.

The previous prime is 79719698593. The next prime is 79719698659. The reversal of 79719698657 is 75689691797.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78069389281 + 1650309376 = 279409^2 + 40624^2 .

It is a cyclic number.

It is not a de Polignac number, because 79719698657 - 2⁶ = 79719698593 is a prime.

Together with 79719698659, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (79719698659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39859849328 + 39859849329.

It is an arithmetic number, because the mean of its divisors is an integer number (39859849329).

Almost surely, 2^79719698657 is an apocalyptic number.

It is an amenable number.

79719698657 is a deficient number, since it is larger than the sum of its proper divisors (1).

79719698657 is an equidigital number, since it uses as much as digits as its factorization.

79719698657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 360067680, while the sum is 74.

The spelling of 79719698657 in words is "seventy-nine billion, seven hundred nineteen million, six hundred ninety-eight thousand, six hundred fifty-seven".