31994539 has 2 divisors, whose sum is σ = 31994540. Its totient is φ = 31994538.

The previous prime is 31994533. The next prime is 31994549. The reversal of 31994539 is 93549913.

It is a weak prime.

It is an emirp because it is prime and its reverse (93549913) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31994539 - 2⁵ = 31994507 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31994495 and 31994504.

It is not a weakly prime, because it can be changed into another prime (31994533) 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, 15997269 + 15997270.

It is an arithmetic number, because the mean of its divisors is an integer number (15997270).

Almost surely, 2^31994539 is an apocalyptic number.

31994539 is a deficient number, since it is larger than the sum of its proper divisors (1).

31994539 is an equidigital number, since it uses as much as digits as its factorization.

31994539 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 131220, while the sum is 43.

The square root of 31994539 is about 5656.3715401307. The cubic root of 31994539 is about 317.4621493721.

The spelling of 31994539 in words is "thirty-one million, nine hundred ninety-four thousand, five hundred thirty-nine".