251955 has 24 divisors (see below), whose sum is σ = 477360. Its totient is φ = 121920.

The previous prime is 251947. The next prime is 251969. The reversal of 251955 is 559152.

It is not a de Polignac number, because 251955 - 2³ = 251947 is a prime.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 251955.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 241 + ... + 749.

It is an arithmetic number, because the mean of its divisors is an integer number (19890).

2²⁵¹⁹⁵⁵ is an apocalyptic number.

251955 is a deficient number, since it is larger than the sum of its proper divisors (225405).

251955 is a wasteful number, since it uses less digits than its factorization.

251955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 531 (or 528 counting only the distinct ones).

The product of its digits is 2250, while the sum is 27.

The square root of 251955 is about 501.9511928465. The cubic root of 251955 is about 63.1598360149.

It can be divided in two parts, 25195 and 5, that added together give a triangular number (25200 = T₂₂₄).

The spelling of 251955 in words is "two hundred fifty-one thousand, nine hundred fifty-five".