25631540 has 24 divisors (see below), whose sum is σ = 58720032. Its totient is φ = 9320480.

The previous prime is 25631533. The next prime is 25631549. The reversal of 25631540 is 4513652.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25631549) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58034 + ... + 58473.

It is an arithmetic number, because the mean of its divisors is an integer number (2446668).

Almost surely, 2^25631540 is an apocalyptic number.

25631540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25631540 is an abundant number, since it is smaller than the sum of its proper divisors (33088492).

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

25631540 is a wasteful number, since it uses less digits than its factorization.

25631540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116527 (or 116525 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 25631540 is about 5062.7601167742. The cubic root of 25631540 is about 294.8435060035.

The spelling of 25631540 in words is "twenty-five million, six hundred thirty-one thousand, five hundred forty".