131981556 has 24 divisors (see below), whose sum is σ = 351951040. Its totient is φ = 37708992.

The previous prime is 131981461. The next prime is 131981561. The reversal of 131981556 is 655189131.

It is a super-2 number, since 2×131981556² = 34838262248362272, which contains 22 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 785521 + ... + 785688.

Almost surely, 2^131981556 is an apocalyptic number.

It is an amenable number.

131981556 is an abundant number, since it is smaller than the sum of its proper divisors (219969484).

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

131981556 is a wasteful number, since it uses less digits than its factorization.

131981556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1571223 (or 1571221 counting only the distinct ones).

The product of its digits is 32400, while the sum is 39.

The square root of 131981556 is about 11488.3225929637. The cubic root of 131981556 is about 509.1406211466.

The spelling of 131981556 in words is "one hundred thirty-one million, nine hundred eighty-one thousand, five hundred fifty-six".