31640039 has 2 divisors, whose sum is σ = 31640040. Its totient is φ = 31640038.

The previous prime is 31640033. The next prime is 31640129. The reversal of 31640039 is 93004613.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31640039 - 2⁴ = 31640023 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31640033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15820019 + 15820020.

It is an arithmetic number, because the mean of its divisors is an integer number (15820020).

Almost surely, 2^31640039 is an apocalyptic number.

31640039 is a deficient number, since it is larger than the sum of its proper divisors (1).

31640039 is an equidigital number, since it uses as much as digits as its factorization.

31640039 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 26.

The square root of 31640039 is about 5624.9479108699. The cubic root of 31640039 is about 316.2852968774.

The spelling of 31640039 in words is "thirty-one million, six hundred forty thousand, thirty-nine".