77251613687657 has 2 divisors, whose sum is σ = 77251613687658. Its totient is φ = 77251613687656.

The previous prime is 77251613687509. The next prime is 77251613687669. The reversal of 77251613687657 is 75678631615277.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52405017635161 + 24846596052496 = 7239131^2 + 4984636^2 .

It is a cyclic number.

It is not a de Polignac number, because 77251613687657 - 2²⁰ = 77251612639081 is a prime.

It is not a weakly prime, because it can be changed into another prime (77251613687257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38625806843828 + 38625806843829.

It is an arithmetic number, because the mean of its divisors is an integer number (38625806843829).

Almost surely, 2^{77251613687657} is an apocalyptic number.

It is an amenable number.

77251613687657 is a deficient number, since it is larger than the sum of its proper divisors (1).

77251613687657 is an equidigital number, since it uses as much as digits as its factorization.

77251613687657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 622339200, while the sum is 71.

The spelling of 77251613687657 in words is "seventy-seven trillion, two hundred fifty-one billion, six hundred thirteen million, six hundred eighty-seven thousand, six hundred fifty-seven".