997513831 has 2 divisors, whose sum is σ = 997513832. Its totient is φ = 997513830.

The previous prime is 997513823. The next prime is 997513849. The reversal of 997513831 is 138315799.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (138315799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 997513831 - 2³ = 997513823 is a prime.

It is a super-2 number, since 2×997513831² = 1990067686072593122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (997513031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498756915 + 498756916.

It is an arithmetic number, because the mean of its divisors is an integer number (498756916).

Almost surely, 2^997513831 is an apocalyptic number.

997513831 is a deficient number, since it is larger than the sum of its proper divisors (1).

997513831 is an equidigital number, since it uses as much as digits as its factorization.

997513831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 204120, while the sum is 46.

The square root of 997513831 is about 31583.4423551329. The cubic root of 997513831 is about 999.1705892680.

The spelling of 997513831 in words is "nine hundred ninety-seven million, five hundred thirteen thousand, eight hundred thirty-one".