668666880 has 352 divisors, whose sum is σ = 2719726080. Its totient is φ = 152616960.

The previous prime is 668666857. The next prime is 668666927. The reversal of 668666880 is 88666866.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 967335 + ... + 968025.

Almost surely, 2^668666880 is an apocalyptic number.

668666880 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 668666880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1359863040).

668666880 is an abundant number, since it is smaller than the sum of its proper divisors (2051059200).

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

668666880 is a wasteful number, since it uses less digits than its factorization.

668666880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 732 (or 708 counting only the distinct ones).

The product of its (nonzero) digits is 3981312, while the sum is 54.

The square root of 668666880 is about 25858.5939292917. The cubic root of 668666880 is about 874.4532660696.

The spelling of 668666880 in words is "six hundred sixty-eight million, six hundred sixty-six thousand, eight hundred eighty".