31312123011217 has 2 divisors, whose sum is σ = 31312123011218. Its totient is φ = 31312123011216.

The previous prime is 31312123011137. The next prime is 31312123011251. The reversal of 31312123011217 is 71211032121313.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25859706539536 + 5452416471681 = 5085244^2 + 2335041^2 .

It is a cyclic number.

It is not a de Polignac number, because 31312123011217 - 2¹⁹ = 31312122486929 is a prime.

It is not a weakly prime, because it can be changed into another prime (31312123012217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15656061505608 + 15656061505609.

It is an arithmetic number, because the mean of its divisors is an integer number (15656061505609).

Almost surely, 2^{31312123011217} is an apocalyptic number.

It is an amenable number.

31312123011217 is a deficient number, since it is larger than the sum of its proper divisors (1).

31312123011217 is an equidigital number, since it uses as much as digits as its factorization.

31312123011217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1512, while the sum is 28.

The spelling of 31312123011217 in words is "thirty-one trillion, three hundred twelve billion, one hundred twenty-three million, eleven thousand, two hundred seventeen".