997959731 has 2 divisors, whose sum is σ = 997959732. Its totient is φ = 997959730.

The previous prime is 997959691. The next prime is 997959749. The reversal of 997959731 is 137959799.

It is a strong prime.

It is an emirp because it is prime and its reverse (137959799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 997959731 - 2²² = 993765427 is a prime.

It is a super-2 number, since 2×997959731² = 1991847249395184722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (997959751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498979865 + 498979866.

It is an arithmetic number, because the mean of its divisors is an integer number (498979866).

Almost surely, 2^997959731 is an apocalyptic number.

997959731 is a deficient number, since it is larger than the sum of its proper divisors (1).

997959731 is an equidigital number, since it uses as much as digits as its factorization.

997959731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4822335, while the sum is 59.

The square root of 997959731 is about 31590.5006449724. The cubic root of 997959731 is about 999.3194472864.

The spelling of 997959731 in words is "nine hundred ninety-seven million, nine hundred fifty-nine thousand, seven hundred thirty-one".