668389922 has 18 divisors (see below), whose sum is σ = 1018235187. Its totient is φ = 329058000.

The previous prime is 668389919. The next prime is 668389927. The reversal of 668389922 is 229983866.

It is a happy number.

668389922 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 5 ways, for example, as 271623361 + 396766561 = 16481^2 + 19919^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=18281.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (668389927) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3692672 + ... + 3692852.

Almost surely, 2^668389922 is an apocalyptic number.

668389922 is a deficient number, since it is larger than the sum of its proper divisors (349845265).

668389922 is an equidigital number, since it uses as much as digits as its factorization.

668389922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 566 (or 284 counting only the distinct ones).

The product of its digits is 2239488, while the sum is 53.

The square root of 668389922 is about 25853.2381337426. The cubic root of 668389922 is about 874.3325182154.

The spelling of 668389922 in words is "six hundred sixty-eight million, three hundred eighty-nine thousand, nine hundred twenty-two".