31305856913 has 2 divisors, whose sum is σ = 31305856914. Its totient is φ = 31305856912.

The previous prime is 31305856871. The next prime is 31305856937. The reversal of 31305856913 is 31965850313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16813790224 + 14492066689 = 129668^2 + 120383^2 .

It is a cyclic number.

It is not a de Polignac number, because 31305856913 - 2⁶ = 31305856849 is a prime.

It is not a weakly prime, because it can be changed into another prime (31305856213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15652928456 + 15652928457.

It is an arithmetic number, because the mean of its divisors is an integer number (15652928457).

Almost surely, 2^31305856913 is an apocalyptic number.

It is an amenable number.

31305856913 is a deficient number, since it is larger than the sum of its proper divisors (1).

31305856913 is an equidigital number, since it uses as much as digits as its factorization.

31305856913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 291600, while the sum is 44.

The spelling of 31305856913 in words is "thirty-one billion, three hundred five million, eight hundred fifty-six thousand, nine hundred thirteen".