131979931 has 2 divisors, whose sum is σ = 131979932. Its totient is φ = 131979930.

The previous prime is 131979929. The next prime is 131979937. The reversal of 131979931 is 139979131.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (139979131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131979931 - 2¹ = 131979929 is a prime.

It is a super-2 number, since 2×131979931² = 34837404373529522, which contains 22 as substring.

Together with 131979929, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (131979937) 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 as a sum of consecutive naturals, namely, 65989965 + 65989966.

It is an arithmetic number, because the mean of its divisors is an integer number (65989966).

Almost surely, 2^131979931 is an apocalyptic number.

131979931 is a deficient number, since it is larger than the sum of its proper divisors (1).

131979931 is an equidigital number, since it uses as much as digits as its factorization.

131979931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45927, while the sum is 43.

The square root of 131979931 is about 11488.2518687571. The cubic root of 131979931 is about 509.1385315695.

The spelling of 131979931 in words is "one hundred thirty-one million, nine hundred seventy-nine thousand, nine hundred thirty-one".