78695657 has 2 divisors, whose sum is σ = 78695658. Its totient is φ = 78695656.

The previous prime is 78695653. The next prime is 78695671. The reversal of 78695657 is 75659687.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70291456 + 8404201 = 8384^2 + 2899^2 .

It is a cyclic number.

It is not a de Polignac number, because 78695657 - 2² = 78695653 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 78695599 and 78695608.

It is not a weakly prime, because it can be changed into another prime (78695651) 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, 39347828 + 39347829.

It is an arithmetic number, because the mean of its divisors is an integer number (39347829).

Almost surely, 2^78695657 is an apocalyptic number.

It is an amenable number.

78695657 is a deficient number, since it is larger than the sum of its proper divisors (1).

78695657 is an equidigital number, since it uses as much as digits as its factorization.

78695657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3175200, while the sum is 53.

The square root of 78695657 is about 8871.0572650615. The cubic root of 78695657 is about 428.5323263319.

The spelling of 78695657 in words is "seventy-eight million, six hundred ninety-five thousand, six hundred fifty-seven".