77687657 has 2 divisors, whose sum is σ = 77687658. Its totient is φ = 77687656.

The previous prime is 77687641. The next prime is 77687669. The reversal of 77687657 is 75678677.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77510416 + 177241 = 8804^2 + 421^2 .

It is a cyclic number.

It is not a de Polignac number, because 77687657 - 2⁴ = 77687641 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 77687599 and 77687608.

It is not a weakly prime, because it can be changed into another prime (77687677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38843828 + 38843829.

It is an arithmetic number, because the mean of its divisors is an integer number (38843829).

Almost surely, 2^77687657 is an apocalyptic number.

It is an amenable number.

77687657 is a deficient number, since it is larger than the sum of its proper divisors (1).

77687657 is an equidigital number, since it uses as much as digits as its factorization.

77687657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3457440, while the sum is 53.

The square root of 77687657 is about 8814.0601881312. The cubic root of 77687657 is about 426.6947911013.

The spelling of 77687657 in words is "seventy-seven million, six hundred eighty-seven thousand, six hundred fifty-seven".