668299816 has 16 divisors (see below), whose sum is σ = 1270228500. Its totient is φ = 329572224.

The previous prime is 668299813. The next prime is 668299817. The reversal of 668299816 is 618992866.

668299816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 667188900 + 1110916 = 25830^2 + 1054^2 .

It is not an unprimeable number, because it can be changed into a prime (668299811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 571591 + ... + 572758.

Almost surely, 2^668299816 is an apocalyptic number.

It is an amenable number.

668299816 is a deficient number, since it is larger than the sum of its proper divisors (601928684).

668299816 is a wasteful number, since it uses less digits than its factorization.

668299816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1144428 (or 1144424 counting only the distinct ones).

The product of its digits is 2239488, while the sum is 55.

The square root of 668299816 is about 25851.4954306322. The cubic root of 668299816 is about 874.2932267062.

The spelling of 668299816 in words is "six hundred sixty-eight million, two hundred ninety-nine thousand, eight hundred sixteen".