131582981 has 4 divisors (see below), whose sum is σ = 134792364. Its totient is φ = 128373600.

The previous prime is 131582959. The next prime is 131582993. The reversal of 131582981 is 189285131.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 60450625 + 71132356 = 7775^2 + 8434^2 .

It is a cyclic number.

It is not a de Polignac number, because 131582981 - 2²⁶ = 64474117 is a prime.

It is a super-2 number, since 2×131582981² = 34628161777692722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131582911) 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, 1604630 + ... + 1604711.

It is an arithmetic number, because the mean of its divisors is an integer number (33698091).

Almost surely, 2^131582981 is an apocalyptic number.

It is an amenable number.

131582981 is a deficient number, since it is larger than the sum of its proper divisors (3209383).

131582981 is an equidigital number, since it uses as much as digits as its factorization.

131582981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3209382.

The product of its digits is 17280, while the sum is 38.

The square root of 131582981 is about 11470.9625141049. The cubic root of 131582981 is about 508.6275814172.

The spelling of 131582981 in words is "one hundred thirty-one million, five hundred eighty-two thousand, nine hundred eighty-one".