668138800 has 180 divisors, whose sum is σ = 1939082736.
Its totient is φ = 216691200.
The previous prime is 668138789. The next prime is 668138803. The reversal of 668138800 is 8831866.
It is a Harshad number since it is a multiple of its sum of digits (40).
It is not an unprimeable number, because it can be changed into a prime (668138803) 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 35 ways as a sum of consecutive naturals, for example, 1010470 + ... + 1011130.
Almost surely, 2668138800 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 668138800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (969541368).
668138800 is an abundant number, since it is smaller than the sum of its proper divisors (1270943936).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
668138800 is a wasteful number, since it uses less digits than its factorization.
668138800 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 724 (or 694 counting only the distinct ones).
The product of its (nonzero) digits is 55296, while the sum is 40.
The square root of 668138800 is about 25848.3809937876.
The cubic root of 668138800 is about 874.2230054760.
The spelling of 668138800 in words is "six hundred sixty-eight million, one hundred thirty-eight thousand, eight hundred".