666668928 has 64 divisors (see below), whose sum is σ = 1775289600. Its totient is φ = 221664768.

The previous prime is 666668917. The next prime is 666668963. The reversal of 666668928 is 829866666.

666668928 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (64).

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, 168153 + ... + 172071.

It is an arithmetic number, because the mean of its divisors is an integer number (27738900).

Almost surely, 2^666668928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666668928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (887644800).

666668928 is an abundant number, since it is smaller than the sum of its proper divisors (1108620672).

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

666668928 is a wasteful number, since it uses less digits than its factorization.

666668928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4379 (or 4367 counting only the distinct ones).

The product of its digits is 8957952, while the sum is 57.

The square root of 666668928 is about 25819.9327652107. The cubic root of 666668928 is about 873.5814524635.

The spelling of 666668928 in words is "six hundred sixty-six million, six hundred sixty-eight thousand, nine hundred twenty-eight".