31131943 has 2 divisors, whose sum is σ = 31131944. Its totient is φ = 31131942.

The previous prime is 31131929. The next prime is 31131953. The reversal of 31131943 is 34913113.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31131943 - 2⁹ = 31131431 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31131953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15565971 + 15565972.

It is an arithmetic number, because the mean of its divisors is an integer number (15565972).

Almost surely, 2^31131943 is an apocalyptic number.

31131943 is a deficient number, since it is larger than the sum of its proper divisors (1).

31131943 is an equidigital number, since it uses as much as digits as its factorization.

31131943 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 972, while the sum is 25.

The square root of 31131943 is about 5579.6006129471. The cubic root of 31131943 is about 314.5831152706.

The spelling of 31131943 in words is "thirty-one million, one hundred thirty-one thousand, nine hundred forty-three".