257978 has 8 divisors (see below), whose sum is σ = 442272. Its totient is φ = 110556.

The previous prime is 257953. The next prime is 257981. The reversal of 257978 is 879752.

It is a sphenic number, since it is the product of 3 distinct primes.

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, 9200 + ... + 9227.

It is an arithmetic number, because the mean of its divisors is an integer number (55284).

2²⁵⁷⁹⁷⁸ is an apocalyptic number.

257978 is a deficient number, since it is larger than the sum of its proper divisors (184294).

257978 is a wasteful number, since it uses less digits than its factorization.

257978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18436.

The product of its digits is 35280, while the sum is 38.

The square root of 257978 is about 507.9153472775. The cubic root of 257978 is about 63.6591580679.

The spelling of 257978 in words is "two hundred fifty-seven thousand, nine hundred seventy-eight".