78257992 has 16 divisors (see below), whose sum is σ = 147054960. Its totient is φ = 39043344.

The previous prime is 78257989. The next prime is 78258041. The reversal of 78257992 is 29975287.

It is a super-2 number, since 2×78257992² = 12248626623744128, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6738 + ... + 14209.

It is an arithmetic number, because the mean of its divisors is an integer number (9190935).

Almost surely, 2^78257992 is an apocalyptic number.

It is an amenable number.

78257992 is a deficient number, since it is larger than the sum of its proper divisors (68796968).

78257992 is a wasteful number, since it uses less digits than its factorization.

78257992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21420 (or 21416 counting only the distinct ones).

The product of its digits is 635040, while the sum is 49.

The square root of 78257992 is about 8846.3547294917. The cubic root of 78257992 is about 427.7364231507.

The spelling of 78257992 in words is "seventy-eight million, two hundred fifty-seven thousand, nine hundred ninety-two".