157931 has 2 divisors, whose sum is σ = 157932. Its totient is φ = 157930.

The previous prime is 157907. The next prime is 157933. The reversal of 157931 is 139751.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 157931 - 2⁶ = 157867 is a prime.

It is a super-2 number, since 2×157931² = 49884401522, which contains 22 as substring.

Together with 157933, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 157931.

It is not a weakly prime, because it can be changed into another prime (157933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78965 + 78966.

It is an arithmetic number, because the mean of its divisors is an integer number (78966).

2¹⁵⁷⁹³¹ is an apocalyptic number.

157931 is a deficient number, since it is larger than the sum of its proper divisors (1).

157931 is an equidigital number, since it uses as much as digits as its factorization.

157931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 945, while the sum is 26.

The square root of 157931 is about 397.4053346396. The cubic root of 157931 is about 54.0533309430.

The spelling of 157931 in words is "one hundred fifty-seven thousand, nine hundred thirty-one".