315137731 has 2 divisors, whose sum is σ = 315137732. Its totient is φ = 315137730.

The previous prime is 315137729. The next prime is 315137737. The reversal of 315137731 is 137731513.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 315137731 - 2¹ = 315137729 is a prime.

It is a super-2 number, since 2×315137731² = 198623578999656722, which contains 22 as substring.

Together with 315137729, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 315137693 and 315137702.

It is not a weakly prime, because it can be changed into another prime (315137737) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157568865 + 157568866.

It is an arithmetic number, because the mean of its divisors is an integer number (157568866).

Almost surely, 2^315137731 is an apocalyptic number.

315137731 is a deficient number, since it is larger than the sum of its proper divisors (1).

315137731 is an equidigital number, since it uses as much as digits as its factorization.

315137731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6615, while the sum is 31.

The square root of 315137731 is about 17752.1190566084. The cubic root of 315137731 is about 680.5083648080.

The spelling of 315137731 in words is "three hundred fifteen million, one hundred thirty-seven thousand, seven hundred thirty-one".