668002006728 has 256 divisors, whose sum is σ = 2171424153600. Its totient is φ = 186339605760.

The previous prime is 668002006723. The next prime is 668002006739. The reversal of 668002006728 is 827600200866.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (668002006723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11027050 + ... + 11087462.

It is an arithmetic number, because the mean of its divisors is an integer number (8482125600).

Almost surely, 2^668002006728 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 668002006728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1085712076800).

668002006728 is an abundant number, since it is smaller than the sum of its proper divisors (1503422146872).

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

668002006728 is a wasteful number, since it uses less digits than its factorization.

668002006728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60609 (or 60599 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The spelling of 668002006728 in words is "six hundred sixty-eight billion, two million, six thousand, seven hundred twenty-eight".