257631 has 16 divisors (see below), whose sum is σ = 386688. Its totient is φ = 151200.

The previous prime is 257627. The next prime is 257639. The reversal of 257631 is 136752.

It is not a de Polignac number, because 257631 - 2² = 257627 is a prime.

It is a super-2 number, since 2×257631² = 132747464322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257639) 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, 1116 + ... + 1326.

It is an arithmetic number, because the mean of its divisors is an integer number (24168).

2²⁵⁷⁶³¹ is an apocalyptic number.

257631 is a deficient number, since it is larger than the sum of its proper divisors (129057).

257631 is a wasteful number, since it uses less digits than its factorization.

257631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262.

The product of its digits is 1260, while the sum is 24.

The square root of 257631 is about 507.5736399775. The cubic root of 257631 is about 63.6306031273.

It can be divided in two parts, 257 and 631, that added together give a palindrome (888).

The spelling of 257631 in words is "two hundred fifty-seven thousand, six hundred thirty-one".