131556640 has 24 divisors (see below), whose sum is σ = 310802940. Its totient is φ = 52622592.

The previous prime is 131556637. The next prime is 131556643. The reversal of 131556640 is 46655131.

It is an interprime number because it is at equal distance from previous prime (131556637) and next prime (131556643).

It can be written as a sum of positive squares in 2 ways, for example, as 131515024 + 41616 = 11468^2 + 204^2 .

It is not an unprimeable number, because it can be changed into a prime (131556643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 410955 + ... + 411274.

Almost surely, 2^131556640 is an apocalyptic number.

131556640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

131556640 is an abundant number, since it is smaller than the sum of its proper divisors (179246300).

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

131556640 is an equidigital number, since it uses as much as digits as its factorization.

131556640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 822244 (or 822236 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 131556640 is about 11469.8142966658. The cubic root of 131556640 is about 508.5936392029.

The spelling of 131556640 in words is "one hundred thirty-one million, five hundred fifty-six thousand, six hundred forty".