131538681 has 16 divisors (see below), whose sum is σ = 195059200. Its totient is φ = 87608304.

The previous prime is 131538623. The next prime is 131538689. The reversal of 131538681 is 186835131.

It is not a de Polignac number, because 131538681 - 2¹⁰ = 131537657 is a prime.

It is a super-2 number, since 2×131538681² = 34604849198439522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131538689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40755 + ... + 43863.

It is an arithmetic number, because the mean of its divisors is an integer number (12191200).

Almost surely, 2^131538681 is an apocalyptic number.

It is an amenable number.

131538681 is a deficient number, since it is larger than the sum of its proper divisors (63520519).

131538681 is a wasteful number, since it uses less digits than its factorization.

131538681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4685 (or 4679 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 131538681 is about 11469.0313889186. The cubic root of 131538681 is about 508.5704951821.

The spelling of 131538681 in words is "one hundred thirty-one million, five hundred thirty-eight thousand, six hundred eighty-one".