115931 has 2 divisors, whose sum is σ = 115932. Its totient is φ = 115930.

The previous prime is 115903. The next prime is 115933. The reversal of 115931 is 139511.

It is a strong prime.

It is an emirp because it is prime and its reverse (139511) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-115931 is a prime.

It is a super-2 number, since 2×115931² = 26879993522, which contains 22 as substring.

Together with 115933, it forms a pair of twin primes.

It is a Chen prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 115931.

It is not a weakly prime, because it can be changed into another prime (115933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57965 + 57966.

It is an arithmetic number, because the mean of its divisors is an integer number (57966).

2¹¹⁵⁹³¹ is an apocalyptic number.

115931 is a deficient number, since it is larger than the sum of its proper divisors (1).

115931 is an equidigital number, since it uses as much as digits as its factorization.

115931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 135, while the sum is 20.

The square root of 115931 is about 340.4864167628. The cubic root of 115931 is about 48.7603177811.

The spelling of 115931 in words is "one hundred fifteen thousand, nine hundred thirty-one".