64977696397 has 2 divisors, whose sum is σ = 64977696398. Its totient is φ = 64977696396.

The previous prime is 64977696389. The next prime is 64977696401. The reversal of 64977696397 is 79369677946.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 32871865636 + 32105830761 = 181306^2 + 179181^2 .

It is a cyclic number.

It is not a de Polignac number, because 64977696397 - 2³ = 64977696389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64977696337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32488848198 + 32488848199.

It is an arithmetic number, because the mean of its divisors is an integer number (32488848199).

Almost surely, 2^64977696397 is an apocalyptic number.

It is an amenable number.

64977696397 is a deficient number, since it is larger than the sum of its proper divisors (1).

64977696397 is an equidigital number, since it uses as much as digits as its factorization.

64977696397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648121824, while the sum is 73.

The spelling of 64977696397 in words is "sixty-four billion, nine hundred seventy-seven million, six hundred ninety-six thousand, three hundred ninety-seven".