815923913731 has 2 divisors, whose sum is σ = 815923913732. Its totient is φ = 815923913730.

The previous prime is 815923913653. The next prime is 815923913807. The reversal of 815923913731 is 137319329518.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-815923913731 is a prime.

It is a super-2 number, since 2×815923913731² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (815923914731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 407961956865 + 407961956866.

It is an arithmetic number, because the mean of its divisors is an integer number (407961956866).

Almost surely, 2^815923913731 is an apocalyptic number.

815923913731 is a deficient number, since it is larger than the sum of its proper divisors (1).

815923913731 is an equidigital number, since it uses as much as digits as its factorization.

815923913731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1224720, while the sum is 52.

The spelling of 815923913731 in words is "eight hundred fifteen billion, nine hundred twenty-three million, nine hundred thirteen thousand, seven hundred thirty-one".