668068128 has 384 divisors, whose sum is σ = 2489356800. Its totient is φ = 169537536.

The previous prime is 668068117. The next prime is 668068153. The reversal of 668068128 is 821860866.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2279950 + ... + 2280242.

It is an arithmetic number, because the mean of its divisors is an integer number (6482700).

Almost surely, 2^668068128 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 668068128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1244678400).

668068128 is an abundant number, since it is smaller than the sum of its proper divisors (1821288672).

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

668068128 is a wasteful number, since it uses less digits than its factorization.

668068128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361 (or 347 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The square root of 668068128 is about 25847.0139087671. The cubic root of 668068128 is about 874.1921809095.

The spelling of 668068128 in words is "six hundred sixty-eight million, sixty-eight thousand, one hundred twenty-eight".