78712657 has 2 divisors, whose sum is σ = 78712658. Its totient is φ = 78712656.

The previous prime is 78712643. The next prime is 78712679. The reversal of 78712657 is 75621787.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73942801 + 4769856 = 8599^2 + 2184^2 .

It is a cyclic number.

It is not a de Polignac number, because 78712657 - 2¹¹ = 78710609 is a prime.

It is not a weakly prime, because it can be changed into another prime (78712607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39356328 + 39356329.

It is an arithmetic number, because the mean of its divisors is an integer number (39356329).

Almost surely, 2^78712657 is an apocalyptic number.

It is an amenable number.

78712657 is a deficient number, since it is larger than the sum of its proper divisors (1).

78712657 is an equidigital number, since it uses as much as digits as its factorization.

78712657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 164640, while the sum is 43.

The square root of 78712657 is about 8872.0153854691. The cubic root of 78712657 is about 428.5631815926.

The spelling of 78712657 in words is "seventy-eight million, seven hundred twelve thousand, six hundred fifty-seven".