668217 has 8 divisors (see below), whose sum is σ = 972000. Its totient is φ = 404960.

The previous prime is 668209. The next prime is 668221. The reversal of 668217 is 712866.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 668217 - 2³ = 668209 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 668217.

It is not an unprimeable number, because it can be changed into a prime (668417) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10092 + ... + 10157.

It is an arithmetic number, because the mean of its divisors is an integer number (121500).

2⁶⁶⁸²¹⁷ is an apocalyptic number.

It is an amenable number.

668217 is a deficient number, since it is larger than the sum of its proper divisors (303783).

668217 is a wasteful number, since it uses less digits than its factorization.

668217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20263.

The product of its digits is 4032, while the sum is 30.

The square root of 668217 is about 817.4454110214. The cubic root of 668217 is about 87.4257110950.

The spelling of 668217 in words is "six hundred sixty-eight thousand, two hundred seventeen".