131581520 has 40 divisors (see below), whose sum is σ = 349632384. Its totient is φ = 45113472.

The previous prime is 131581511. The next prime is 131581523. The reversal of 131581520 is 25185131.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 131581520.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131581523) 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, 116924 + ... + 118043.

Almost surely, 2^131581520 is an apocalyptic number.

131581520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

131581520 is an abundant number, since it is smaller than the sum of its proper divisors (218050864).

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

131581520 is a wasteful number, since it uses less digits than its factorization.

131581520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234987 (or 234981 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 26.

The square root of 131581520 is about 11470.8988313907. The cubic root of 131581520 is about 508.6256989356.

The spelling of 131581520 in words is "one hundred thirty-one million, five hundred eighty-one thousand, five hundred twenty".