311121312217 has 2 divisors, whose sum is σ = 311121312218. Its totient is φ = 311121312216.

The previous prime is 311121312127. The next prime is 311121312239. The reversal of 311121312217 is 712213121113.

Together with previous prime (311121312127) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 310587748416 + 533563801 = 557304^2 + 23099^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311121312217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 311121312191 and 311121312200.

It is not a weakly prime, because it can be changed into another prime (311121316217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155560656108 + 155560656109.

It is an arithmetic number, because the mean of its divisors is an integer number (155560656109).

Almost surely, 2^311121312217 is an apocalyptic number.

It is an amenable number.

311121312217 is a deficient number, since it is larger than the sum of its proper divisors (1).

311121312217 is an equidigital number, since it uses as much as digits as its factorization.

311121312217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 504, while the sum is 25.

The spelling of 311121312217 in words is "three hundred eleven billion, one hundred twenty-one million, three hundred twelve thousand, two hundred seventeen".