668354817 has 16 divisors (see below), whose sum is σ = 983098368. Its totient is φ = 401262720.

The previous prime is 668354807. The next prime is 668354821. The reversal of 668354817 is 718453866.

It is not a de Polignac number, because 668354817 - 2⁴ = 668354801 is a prime.

It is a super-2 number, since 2×668354817² = 893396322814206978, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (668354807) 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 in 15 ways as a sum of consecutive naturals, for example, 207393 + ... + 210590.

It is an arithmetic number, because the mean of its divisors is an integer number (61443648).

Almost surely, 2^668354817 is an apocalyptic number.

It is an amenable number.

668354817 is a deficient number, since it is larger than the sum of its proper divisors (314743551).

668354817 is a wasteful number, since it uses less digits than its factorization.

668354817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418040.

The product of its digits is 967680, while the sum is 48.

The square root of 668354817 is about 25852.5591963349. The cubic root of 668354817 is about 874.3172107931.

The spelling of 668354817 in words is "six hundred sixty-eight million, three hundred fifty-four thousand, eight hundred seventeen".