31105309 has 2 divisors, whose sum is σ = 31105310. Its totient is φ = 31105308.

The previous prime is 31105259. The next prime is 31105339. The reversal of 31105309 is 90350113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18679684 + 12425625 = 4322^2 + 3525^2 .

It is a cyclic number.

It is not a de Polignac number, because 31105309 - 2¹³ = 31097117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31105309.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31105339) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15552654 + 15552655.

It is an arithmetic number, because the mean of its divisors is an integer number (15552655).

Almost surely, 2^31105309 is an apocalyptic number.

It is an amenable number.

31105309 is a deficient number, since it is larger than the sum of its proper divisors (1).

31105309 is an equidigital number, since it uses as much as digits as its factorization.

31105309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 405, while the sum is 22.

The square root of 31105309 is about 5577.2133722855. The cubic root of 31105309 is about 314.4933789593.

The spelling of 31105309 in words is "thirty-one million, one hundred five thousand, three hundred nine".