668944384 has 24 divisors (see below), whose sum is σ = 1337566230. Its totient is φ = 334471168.

The previous prime is 668944379. The next prime is 668944403. The reversal of 668944384 is 483449866.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 480486400 + 188457984 = 21920^2 + 13728^2 .

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 as a sum of consecutive naturals, namely, 161269 + ... + 165364.

Almost surely, 2^668944384 is an apocalyptic number.

668944384 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

668944384 is a deficient number, since it is larger than the sum of its proper divisors (668621846).

668944384 is an equidigital number, since it uses as much as digits as its factorization.

668944384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326655 (or 326635 counting only the distinct ones).

The product of its digits is 3981312, while the sum is 52.

The square root of 668944384 is about 25863.9591710163. The cubic root of 668944384 is about 874.5742185323.

The spelling of 668944384 in words is "six hundred sixty-eight million, nine hundred forty-four thousand, three hundred eighty-four".