217298317 has 2 divisors, whose sum is σ = 217298318. Its totient is φ = 217298316.

The previous prime is 217298293. The next prime is 217298321. The reversal of 217298317 is 713892712.

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., 127825636 + 89472681 = 11306^2 + 9459^2 .

It is a cyclic number.

It is not a de Polignac number, because 217298317 - 2¹⁹ = 216774029 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 217298317.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217298377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108649158 + 108649159.

It is an arithmetic number, because the mean of its divisors is an integer number (108649159).

Almost surely, 2^217298317 is an apocalyptic number.

It is an amenable number.

217298317 is a deficient number, since it is larger than the sum of its proper divisors (1).

217298317 is an equidigital number, since it uses as much as digits as its factorization.

217298317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42336, while the sum is 40.

The square root of 217298317 is about 14741.0419238261. The cubic root of 217298317 is about 601.1997447921.

It can be divided in two parts, 2172 and 98317, that added together give a square (100489 = 317²).

The spelling of 217298317 in words is "two hundred seventeen million, two hundred ninety-eight thousand, three hundred seventeen".