31407745217 has 2 divisors, whose sum is σ = 31407745218. Its totient is φ = 31407745216.

The previous prime is 31407745189. The next prime is 31407745219. The reversal of 31407745217 is 71254770413.

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., 31351660096 + 56085121 = 177064^2 + 7489^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31407745217 is a prime.

Together with 31407745219, 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 (31407745219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15703872608 + 15703872609.

It is an arithmetic number, because the mean of its divisors is an integer number (15703872609).

Almost surely, 2^31407745217 is an apocalyptic number.

It is an amenable number.

31407745217 is a deficient number, since it is larger than the sum of its proper divisors (1).

31407745217 is an equidigital number, since it uses as much as digits as its factorization.

31407745217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 164640, while the sum is 41.

The spelling of 31407745217 in words is "thirty-one billion, four hundred seven million, seven hundred forty-five thousand, two hundred seventeen".