668878580 has 12 divisors (see below), whose sum is σ = 1404645060. Its totient is φ = 267551424.

The previous prime is 668878577. The next prime is 668878597. The reversal of 668878580 is 85878866.

It can be written as a sum of positive squares in 2 ways, for example, as 125708944 + 543169636 = 11212^2 + 23306^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16721945 + ... + 16721984.

It is an arithmetic number, because the mean of its divisors is an integer number (117053755).

Almost surely, 2^668878580 is an apocalyptic number.

It is an amenable number.

668878580 is an abundant number, since it is smaller than the sum of its proper divisors (735766480).

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

668878580 is a wasteful number, since it uses less digits than its factorization.

668878580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33443938 (or 33443936 counting only the distinct ones).

The product of its (nonzero) digits is 5160960, while the sum is 56.

The square root of 668878580 is about 25862.6870220401. The cubic root of 668878580 is about 874.5455403290.

The spelling of 668878580 in words is "six hundred sixty-eight million, eight hundred seventy-eight thousand, five hundred eighty".