25531 has 6 divisors (see below), whose sum is σ = 28196. Its totient is φ = 23100.

The previous prime is 25523. The next prime is 25537. The reversal of 25531 is 13552.

It is not a de Polignac number, because 25531 - 2³ = 25523 is a prime.

It is a super-2 number, since 2×25531² = 1303663922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25537) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 16 + ... + 226.

2²⁵⁵³¹ is an apocalyptic number.

25531 is a deficient number, since it is larger than the sum of its proper divisors (2665).

25531 is a wasteful number, since it uses less digits than its factorization.

25531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233 (or 222 counting only the distinct ones).

The product of its digits is 150, while the sum is 16.

The square root of 25531 is about 159.7842295097. The cubic root of 25531 is about 29.4457491873.

The spelling of 25531 in words is "twenty-five thousand, five hundred thirty-one".