31122211217 has 2 divisors, whose sum is σ = 31122211218. Its totient is φ = 31122211216.

The previous prime is 31122211189. The next prime is 31122211247. The reversal of 31122211217 is 71211222113.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28173286801 + 2948924416 = 167849^2 + 54304^2 .

It is a cyclic number.

It is not a de Polignac number, because 31122211217 - 2¹⁰ = 31122210193 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31122211192 and 31122211201.

It is not a weakly prime, because it can be changed into another prime (31122211247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15561105608 + 15561105609.

It is an arithmetic number, because the mean of its divisors is an integer number (15561105609).

Almost surely, 2^31122211217 is an apocalyptic number.

It is an amenable number.

31122211217 is a deficient number, since it is larger than the sum of its proper divisors (1).

31122211217 is an equidigital number, since it uses as much as digits as its factorization.

31122211217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 336, while the sum is 23.

The spelling of 31122211217 in words is "thirty-one billion, one hundred twenty-two million, two hundred eleven thousand, two hundred seventeen".