216317 has 2 divisors, whose sum is σ = 216318. Its totient is φ = 216316.

The previous prime is 216289. The next prime is 216319. The reversal of 216317 is 713612.

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., 206116 + 10201 = 454^2 + 101^2 .

It is a cyclic number.

It is not a de Polignac number, because 216317 - 2⁸ = 216061 is a prime.

Together with 216319, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108158 + 108159.

It is an arithmetic number, because the mean of its divisors is an integer number (108159).

2²¹⁶³¹⁷ is an apocalyptic number.

It is an amenable number.

216317 is a deficient number, since it is larger than the sum of its proper divisors (1).

216317 is an equidigital number, since it uses as much as digits as its factorization.

216317 is an evil number, because the sum of its binary digits is even.

The product of its digits is 252, while the sum is 20.

The square root of 216317 is about 465.0989142107. The cubic root of 216317 is about 60.0293375047.

Adding to 216317 its reverse (713612), we get a palindrome (929929).

The spelling of 216317 in words is "two hundred sixteen thousand, three hundred seventeen".