31312113113 has 2 divisors, whose sum is σ = 31312113114. Its totient is φ = 31312113112.

The previous prime is 31312113109. The next prime is 31312113169. The reversal of 31312113113 is 31131121313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24858882889 + 6453230224 = 157667^2 + 80332^2 .

It is a cyclic number.

It is not a de Polignac number, because 31312113113 - 2² = 31312113109 is a prime.

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 (31312113193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15656056556 + 15656056557.

It is an arithmetic number, because the mean of its divisors is an integer number (15656056557).

Almost surely, 2^31312113113 is an apocalyptic number.

It is an amenable number.

31312113113 is a deficient number, since it is larger than the sum of its proper divisors (1).

31312113113 is an equidigital number, since it uses as much as digits as its factorization.

31312113113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 162, while the sum is 20.

Adding to 31312113113 its reverse (31131121313), we get a palindrome (62443234426).

The spelling of 31312113113 in words is "thirty-one billion, three hundred twelve million, one hundred thirteen thousand, one hundred thirteen".