257391385 has 16 divisors (see below), whose sum is σ = 336340800. Its totient is φ = 188346816.

The previous prime is 257391361. The next prime is 257391403. The reversal of 257391385 is 583193752.

It is a cyclic number.

It is not a de Polignac number, because 257391385 - 2¹⁵ = 257358617 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43959 + ... + 49468.

It is an arithmetic number, because the mean of its divisors is an integer number (21021300).

Almost surely, 2^257391385 is an apocalyptic number.

It is an amenable number.

257391385 is a deficient number, since it is larger than the sum of its proper divisors (78949415).

257391385 is a wasteful number, since it uses less digits than its factorization.

257391385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93480.

The product of its digits is 226800, while the sum is 43.

The square root of 257391385 is about 16043.4218606879. The cubic root of 257391385 is about 636.1087002544.

The spelling of 257391385 in words is "two hundred fifty-seven million, three hundred ninety-one thousand, three hundred eighty-five".