31297913 has 2 divisors, whose sum is σ = 31297914. Its totient is φ = 31297912.

The previous prime is 31297853. The next prime is 31297951. The reversal of 31297913 is 31979213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24522304 + 6775609 = 4952^2 + 2603^2 .

It is a cyclic number.

It is not a de Polignac number, because 31297913 - 2¹⁸ = 31035769 is a prime.

It is not a weakly prime, because it can be changed into another prime (31297213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15648956 + 15648957.

It is an arithmetic number, because the mean of its divisors is an integer number (15648957).

Almost surely, 2^31297913 is an apocalyptic number.

It is an amenable number.

31297913 is a deficient number, since it is larger than the sum of its proper divisors (1).

31297913 is an equidigital number, since it uses as much as digits as its factorization.

31297913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10206, while the sum is 35.

The square root of 31297913 is about 5594.4537713704. The cubic root of 31297913 is about 315.1411578653.

The spelling of 31297913 in words is "thirty-one million, two hundred ninety-seven thousand, nine hundred thirteen".