78686375 has 8 divisors (see below), whose sum is σ = 98200752. Its totient is φ = 62949000.

The previous prime is 78686369. The next prime is 78686411. The reversal of 78686375 is 57368687.

It is not a de Polignac number, because 78686375 - 2¹⁴ = 78669991 is a prime.

It is a super-2 number, since 2×78686375² = 12383091221281250, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 314621 + ... + 314870.

It is an arithmetic number, because the mean of its divisors is an integer number (12275094).

Almost surely, 2^78686375 is an apocalyptic number.

78686375 is a deficient number, since it is larger than the sum of its proper divisors (19514377).

78686375 is an equidigital number, since it uses as much as digits as its factorization.

78686375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 629506 (or 629496 counting only the distinct ones).

The product of its digits is 1693440, while the sum is 50.

The square root of 78686375 is about 8870.5340876409. The cubic root of 78686375 is about 428.5154774841.

The spelling of 78686375 in words is "seventy-eight million, six hundred eighty-six thousand, three hundred seventy-five".