251864 has 16 divisors (see below), whose sum is σ = 497400. Its totient is φ = 119232.

The previous prime is 251861. The next prime is 251879. The reversal of 251864 is 468152.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 677 + ... + 980.

2²⁵¹⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

251864 is a deficient number, since it is larger than the sum of its proper divisors (245536).

251864 is a wasteful number, since it uses less digits than its factorization.

251864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1682 (or 1678 counting only the distinct ones).

The product of its digits is 1920, while the sum is 26.

The square root of 251864 is about 501.8605383969. The cubic root of 251864 is about 63.1522311686.

The spelling of 251864 in words is "two hundred fifty-one thousand, eight hundred sixty-four".