31105323209 has 2 divisors, whose sum is σ = 31105323210. Its totient is φ = 31105323208.

The previous prime is 31105323203. The next prime is 31105323253. The reversal of 31105323209 is 90232350113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26289379600 + 4815943609 = 162140^2 + 69397^2 .

It is a cyclic number.

It is not a de Polignac number, because 31105323209 - 2²⁰ = 31104274633 is a prime.

It is a super-2 number, since 2×31105323209² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (31105323203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15552661604 + 15552661605.

It is an arithmetic number, because the mean of its divisors is an integer number (15552661605).

Almost surely, 2^31105323209 is an apocalyptic number.

It is an amenable number.

31105323209 is a deficient number, since it is larger than the sum of its proper divisors (1).

31105323209 is an equidigital number, since it uses as much as digits as its factorization.

31105323209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4860, while the sum is 29.

The spelling of 31105323209 in words is "thirty-one billion, one hundred five million, three hundred twenty-three thousand, two hundred nine".