31123012313 has 2 divisors, whose sum is σ = 31123012314. Its totient is φ = 31123012312.

The previous prime is 31123012267. The next prime is 31123012363. The reversal of 31123012313 is 31321032113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29850163984 + 1272848329 = 172772^2 + 35677^2 .

It is a cyclic number.

It is not a de Polignac number, because 31123012313 - 2⁸ = 31123012057 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 (31123012363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15561506156 + 15561506157.

It is an arithmetic number, because the mean of its divisors is an integer number (15561506157).

Almost surely, 2^31123012313 is an apocalyptic number.

It is an amenable number.

31123012313 is a deficient number, since it is larger than the sum of its proper divisors (1).

31123012313 is an equidigital number, since it uses as much as digits as its factorization.

31123012313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 31123012313 its reverse (31321032113), we get a palindrome (62444044426).

The spelling of 31123012313 in words is "thirty-one billion, one hundred twenty-three million, twelve thousand, three hundred thirteen".