217390097 has 2 divisors, whose sum is σ = 217390098. Its totient is φ = 217390096.

The previous prime is 217390057. The next prime is 217390099. The reversal of 217390097 is 790093712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 202521361 + 14868736 = 14231^2 + 3856^2 .

It is a cyclic number.

It is not a de Polignac number, because 217390097 - 2⁸ = 217389841 is a prime.

Together with 217390099, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 217390097.

It is not a weakly prime, because it can be changed into another prime (217390099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108695048 + 108695049.

It is an arithmetic number, because the mean of its divisors is an integer number (108695049).

Almost surely, 2^217390097 is an apocalyptic number.

It is an amenable number.

217390097 is a deficient number, since it is larger than the sum of its proper divisors (1).

217390097 is an equidigital number, since it uses as much as digits as its factorization.

217390097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23814, while the sum is 38.

The square root of 217390097 is about 14744.1546722761. The cubic root of 217390097 is about 601.2843755226.

The spelling of 217390097 in words is "two hundred seventeen million, three hundred ninety thousand, ninety-seven".