31840631 has 2 divisors, whose sum is σ = 31840632. Its totient is φ = 31840630.

The previous prime is 31840619. The next prime is 31840649. The reversal of 31840631 is 13604813.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31840631 is a prime.

It is a super-2 number, since 2×31840631² = 2027651564956322, which contains 22 as substring.

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 31840631.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31840681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15920315 + 15920316.

It is an arithmetic number, because the mean of its divisors is an integer number (15920316).

Almost surely, 2^31840631 is an apocalyptic number.

31840631 is a deficient number, since it is larger than the sum of its proper divisors (1).

31840631 is an equidigital number, since it uses as much as digits as its factorization.

31840631 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 31840631 is about 5642.7503045944. The cubic root of 31840631 is about 316.9522861044.

The spelling of 31840631 in words is "thirty-one million, eight hundred forty thousand, six hundred thirty-one".