257904 has 50 divisors (see below), whose sum is σ = 750200. Its totient is φ = 85536.

The previous prime is 257903. The next prime is 257921. The reversal of 257904 is 409752.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nialpdrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257903) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1197 + ... + 1395.

It is an arithmetic number, because the mean of its divisors is an integer number (15004).

2²⁵⁷⁹⁰⁴ is an apocalyptic number.

257904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 257904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (375100).

257904 is an abundant number, since it is smaller than the sum of its proper divisors (492296).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

257904 is a wasteful number, since it uses less digits than its factorization.

257904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 257904 is about 507.8424952680. The cubic root of 257904 is about 63.6530706907.

The spelling of 257904 in words is "two hundred fifty-seven thousand, nine hundred four".