31713989 has 2 divisors, whose sum is σ = 31713990. Its totient is φ = 31713988.

The previous prime is 31713977. The next prime is 31714013. The reversal of 31713989 is 98931713.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30991489 + 722500 = 5567^2 + 850^2 .

It is an emirp because it is prime and its reverse (98931713) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31713989 is a 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 (31913989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15856994 + 15856995.

It is an arithmetic number, because the mean of its divisors is an integer number (15856995).

Almost surely, 2^31713989 is an apocalyptic number.

It is an amenable number.

31713989 is a deficient number, since it is larger than the sum of its proper divisors (1).

31713989 is an equidigital number, since it uses as much as digits as its factorization.

31713989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 41.

The square root of 31713989 is about 5631.5174686757. The cubic root of 31713989 is about 316.5315154876.

The spelling of 31713989 in words is "thirty-one million, seven hundred thirteen thousand, nine hundred eighty-nine".