668006644163 has 4 divisors (see below), whose sum is σ = 668442966168. Its totient is φ = 667570322160.

The previous prime is 668006644147. The next prime is 668006644171. The reversal of 668006644163 is 361446600866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 668006644163 - 2⁴ = 668006644147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (668006644103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218158706 + ... + 218161767.

It is an arithmetic number, because the mean of its divisors is an integer number (167110741542).

Almost surely, 2^668006644163 is an apocalyptic number.

668006644163 is a deficient number, since it is larger than the sum of its proper divisors (436322005).

668006644163 is a wasteful number, since it uses less digits than its factorization.

668006644163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436322004.

The product of its (nonzero) digits is 2985984, while the sum is 50.

The spelling of 668006644163 in words is "six hundred sixty-eight billion, six million, six hundred forty-four thousand, one hundred sixty-three".