131991556 has 48 divisors (see below), whose sum is σ = 251233920. Its totient is φ = 60480000.

The previous prime is 131991533. The next prime is 131991569. The reversal of 131991556 is 655199131.

It is a super-2 number, since 2×131991556² = 34843541710602272, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 328956 + ... + 329356.

It is an arithmetic number, because the mean of its divisors is an integer number (5234040).

Almost surely, 2^131991556 is an apocalyptic number.

It is an amenable number.

131991556 is a deficient number, since it is larger than the sum of its proper divisors (119242364).

131991556 is a wasteful number, since it uses less digits than its factorization.

131991556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556 (or 554 counting only the distinct ones).

The product of its digits is 36450, while the sum is 40.

The square root of 131991556 is about 11488.7578092673. The cubic root of 131991556 is about 509.1534797050.

The spelling of 131991556 in words is "one hundred thirty-one million, nine hundred ninety-one thousand, five hundred fifty-six".