43431931 has 2 divisors, whose sum is σ = 43431932. Its totient is φ = 43431930.

The previous prime is 43431917. The next prime is 43431943. The reversal of 43431931 is 13913434.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43431931 is a prime.

It is a super-2 number, since 2×43431931² = 3772665260777522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 43431931.

It is not a weakly prime, because it can be changed into another prime (43431331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21715965 + 21715966.

It is an arithmetic number, because the mean of its divisors is an integer number (21715966).

Almost surely, 2^43431931 is an apocalyptic number.

43431931 is a deficient number, since it is larger than the sum of its proper divisors (1).

43431931 is an equidigital number, since it uses as much as digits as its factorization.

43431931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 28.

The square root of 43431931 is about 6590.2906612683. The cubic root of 43431931 is about 351.5089436943.

The spelling of 43431931 in words is "forty-three million, four hundred thirty-one thousand, nine hundred thirty-one".