25231531 has 12 divisors (see below), whose sum is σ = 27511488. Its totient is φ = 23129184.

The previous prime is 25231513. The next prime is 25231561. The reversal of 25231531 is 13513252.

It is not a de Polignac number, because 25231531 - 2⁵ = 25231499 is a prime.

It is a super-2 number, since 2×25231531² = 1273260313207922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25231561) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28806 + ... + 29668.

It is an arithmetic number, because the mean of its divisors is an integer number (2292624).

Almost surely, 2^25231531 is an apocalyptic number.

25231531 is a deficient number, since it is larger than the sum of its proper divisors (2279957).

25231531 is a wasteful number, since it uses less digits than its factorization.

25231531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1062 (or 1049 counting only the distinct ones).

The product of its digits is 900, while the sum is 22.

The square root of 25231531 is about 5023.0997402003. The cubic root of 25231531 is about 293.3016691315.

Adding to 25231531 its reverse (13513252), we get a palindrome (38744783).

The spelling of 25231531 in words is "twenty-five million, two hundred thirty-one thousand, five hundred thirty-one".