668516996 has 18 divisors (see below), whose sum is σ = 1360909998. Its totient is φ = 286507200.

The previous prime is 668516977. The next prime is 668517041. The reversal of 668516996 is 699615866.

It can be written as a sum of positive squares in only one way, i.e., 452838400 + 215678596 = 21280^2 + 14686^2 .

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 1705205 + ... + 1705596.

It is an arithmetic number, because the mean of its divisors is an integer number (75606111).

Almost surely, 2^668516996 is an apocalyptic number.

It is an amenable number.

668516996 is an abundant number, since it is smaller than the sum of its proper divisors (692393002).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

668516996 is a wasteful number, since it uses less digits than its factorization.

668516996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3410819 (or 3410810 counting only the distinct ones).

The product of its digits is 4199040, while the sum is 56.

The square root of 668516996 is about 25855.6956201143. The cubic root of 668516996 is about 874.3879239431.

The spelling of 668516996 in words is "six hundred sixty-eight million, five hundred sixteen thousand, nine hundred ninety-six".