257385 has 8 divisors (see below), whose sum is σ = 411840. Its totient is φ = 137264.

The previous prime is 257381. The next prime is 257399. The reversal of 257385 is 583752.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 257385 - 2² = 257381 is a prime.

It is a nialpdrome in base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8565 + ... + 8594.

It is an arithmetic number, because the mean of its divisors is an integer number (51480).

2²⁵⁷³⁸⁵ is an apocalyptic number.

It is an amenable number.

257385 is a deficient number, since it is larger than the sum of its proper divisors (154455).

257385 is a wasteful number, since it uses less digits than its factorization.

257385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17167.

The product of its digits is 8400, while the sum is 30.

The square root of 257385 is about 507.3312527334. The cubic root of 257385 is about 63.6103440317.

The spelling of 257385 in words is "two hundred fifty-seven thousand, three hundred eighty-five".