31908313 has 2 divisors, whose sum is σ = 31908314. Its totient is φ = 31908312.

The previous prime is 31908301. The next prime is 31908329. The reversal of 31908313 is 31380913.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29192409 + 2715904 = 5403^2 + 1648^2 .

It is a cyclic number.

It is not a de Polignac number, because 31908313 - 2¹⁷ = 31777241 is a prime.

It is not a weakly prime, because it can be changed into another prime (31908343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15954156 + 15954157.

It is an arithmetic number, because the mean of its divisors is an integer number (15954157).

Almost surely, 2^31908313 is an apocalyptic number.

It is an amenable number.

31908313 is a deficient number, since it is larger than the sum of its proper divisors (1).

31908313 is an equidigital number, since it uses as much as digits as its factorization.

31908313 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 28.

The square root of 31908313 is about 5648.7443737525. The cubic root of 31908313 is about 317.1767035872.

The spelling of 31908313 in words is "thirty-one million, nine hundred eight thousand, three hundred thirteen".