131979917 has 2 divisors, whose sum is σ = 131979918. Its totient is φ = 131979916.

The previous prime is 131979847. The next prime is 131979929. The reversal of 131979917 is 719979131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 86471401 + 45508516 = 9299^2 + 6746^2 .

It is an emirp because it is prime and its reverse (719979131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131979917 - 2²² = 127785613 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131979937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65989958 + 65989959.

It is an arithmetic number, because the mean of its divisors is an integer number (65989959).

Almost surely, 2^131979917 is an apocalyptic number.

It is an amenable number.

131979917 is a deficient number, since it is larger than the sum of its proper divisors (1).

131979917 is an equidigital number, since it uses as much as digits as its factorization.

131979917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 107163, while the sum is 47.

The square root of 131979917 is about 11488.2512594389. The cubic root of 131979917 is about 509.1385135669.

The spelling of 131979917 in words is "one hundred thirty-one million, nine hundred seventy-nine thousand, nine hundred seventeen".