31322320217 has 2 divisors, whose sum is σ = 31322320218. Its totient is φ = 31322320216.

The previous prime is 31322320201. The next prime is 31322320219. The reversal of 31322320217 is 71202322313.

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., 16482451456 + 14839868761 = 128384^2 + 121819^2 .

It is an emirp because it is prime and its reverse (71202322313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31322320217 - 2⁴ = 31322320201 is a prime.

Together with 31322320219, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31322320219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15661160108 + 15661160109.

It is an arithmetic number, because the mean of its divisors is an integer number (15661160109).

Almost surely, 2^31322320217 is an apocalyptic number.

It is an amenable number.

31322320217 is a deficient number, since it is larger than the sum of its proper divisors (1).

31322320217 is an equidigital number, since it uses as much as digits as its factorization.

31322320217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 26.

The spelling of 31322320217 in words is "thirty-one billion, three hundred twenty-two million, three hundred twenty thousand, two hundred seventeen".