257705 has 16 divisors (see below), whose sum is σ = 364800. Its totient is φ = 171072.

The previous prime is 257689. The next prime is 257707. The reversal of 257705 is 507752.

It is a cyclic number.

It is not a de Polignac number, because 257705 - 2⁴ = 257689 is a prime.

It is a plaindrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (257707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1196 + ... + 1394.

It is an arithmetic number, because the mean of its divisors is an integer number (22800).

2²⁵⁷⁷⁰⁵ is an apocalyptic number.

It is an amenable number.

257705 is a deficient number, since it is larger than the sum of its proper divisors (107095).

257705 is a wasteful number, since it uses less digits than its factorization.

257705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248.

The product of its (nonzero) digits is 2450, while the sum is 26.

The square root of 257705 is about 507.6465305702. The cubic root of 257705 is about 63.6366948035.

Subtracting from 257705 its product of nonzero digits (2450), we obtain a triangular number (255255 = T₇₁₄).

Subtracting 257705 from its reverse (507752), we obtain a cube (250047 = 63³).

The spelling of 257705 in words is "two hundred fifty-seven thousand, seven hundred five".