131531504 has 20 divisors (see below), whose sum is σ = 274445976. Its totient is φ = 60706752.

The previous prime is 131531489. The next prime is 131531557. The reversal of 131531504 is 405135131.

It is a self number, because there is not a number n which added to its sum of digits gives 131531504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 315974 + ... + 316389.

Almost surely, 2^131531504 is an apocalyptic number.

It is an amenable number.

131531504 is an abundant number, since it is smaller than the sum of its proper divisors (142914472).

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

131531504 is a wasteful number, since it uses less digits than its factorization.

131531504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632384 (or 632378 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 23.

The square root of 131531504 is about 11468.7184985943. The cubic root of 131531504 is about 508.5612454902.

Adding to 131531504 its reverse (405135131), we get a palindrome (536666635).

The spelling of 131531504 in words is "one hundred thirty-one million, five hundred thirty-one thousand, five hundred four".