668389628 has 24 divisors (see below), whose sum is σ = 1178210880. Its totient is φ = 331767360.

The previous prime is 668389577. The next prime is 668389639. The reversal of 668389628 is 826983866.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 393950 + ... + 395642.

It is an arithmetic number, because the mean of its divisors is an integer number (49092120).

Almost surely, 2^668389628 is an apocalyptic number.

It is an amenable number.

668389628 is a deficient number, since it is larger than the sum of its proper divisors (509821252).

668389628 is a wasteful number, since it uses less digits than its factorization.

668389628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2357 (or 2355 counting only the distinct ones).

The product of its digits is 5971968, while the sum is 56.

The square root of 668389628 is about 25853.2324478004. The cubic root of 668389628 is about 874.3323900199.

The spelling of 668389628 in words is "six hundred sixty-eight million, three hundred eighty-nine thousand, six hundred twenty-eight".