217930383217 has 2 divisors, whose sum is σ = 217930383218. Its totient is φ = 217930383216.

The previous prime is 217930383197. The next prime is 217930383247. The reversal of 217930383217 is 712383039712.

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., 199209576241 + 18720806976 = 446329^2 + 136824^2 .

It is a cyclic number.

It is not a de Polignac number, because 217930383217 - 2⁷ = 217930383089 is a prime.

It is not a weakly prime, because it can be changed into another prime (217930383247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108965191608 + 108965191609.

It is an arithmetic number, because the mean of its divisors is an integer number (108965191609).

Almost surely, 2^217930383217 is an apocalyptic number.

It is an amenable number.

217930383217 is a deficient number, since it is larger than the sum of its proper divisors (1).

217930383217 is an equidigital number, since it uses as much as digits as its factorization.

217930383217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 381024, while the sum is 46.

The spelling of 217930383217 in words is "two hundred seventeen billion, nine hundred thirty million, three hundred eighty-three thousand, two hundred seventeen".