31113506909 has 2 divisors, whose sum is σ = 31113506910. Its totient is φ = 31113506908.

The previous prime is 31113506839. The next prime is 31113506917. The reversal of 31113506909 is 90960531113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30862759684 + 250747225 = 175678^2 + 15835^2 .

It is a cyclic number.

It is not a de Polignac number, because 31113506909 - 2⁸ = 31113506653 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31113506939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15556753454 + 15556753455.

It is an arithmetic number, because the mean of its divisors is an integer number (15556753455).

Almost surely, 2^31113506909 is an apocalyptic number.

It is an amenable number.

31113506909 is a deficient number, since it is larger than the sum of its proper divisors (1).

31113506909 is an equidigital number, since it uses as much as digits as its factorization.

31113506909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21870, while the sum is 38.

The spelling of 31113506909 in words is "thirty-one billion, one hundred thirteen million, five hundred six thousand, nine hundred nine".