78565257 has 12 divisors (see below), whose sum is σ = 116122864. Its totient is φ = 51158520.

The previous prime is 78565243. The next prime is 78565271. The reversal of 78565257 is 75256587.

78565257 is a `hidden beast` number, since 78 + 56 + 525 + 7 = 666.

It is an interprime number because it is at equal distance from previous prime (78565243) and next prime (78565271).

It is not a de Polignac number, because 78565257 - 2¹⁶ = 78499721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78565297) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 101119 + ... + 101892.

Almost surely, 2^78565257 is an apocalyptic number.

It is an amenable number.

78565257 is a deficient number, since it is larger than the sum of its proper divisors (37557607).

78565257 is a wasteful number, since it uses less digits than its factorization.

78565257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203060 (or 203057 counting only the distinct ones).

The product of its digits is 588000, while the sum is 45.

The square root of 78565257 is about 8863.7044738642. The cubic root of 78565257 is about 428.2955004343.

The spelling of 78565257 in words is "seventy-eight million, five hundred sixty-five thousand, two hundred fifty-seven".