668836660 has 12 divisors (see below), whose sum is σ = 1404557028. Its totient is φ = 267534656.

The previous prime is 668836639. The next prime is 668836669. The reversal of 668836660 is 66638866.

It can be written as a sum of positive squares in 2 ways, for example, as 415262884 + 253573776 = 20378^2 + 15924^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668836669) 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 3 ways as a sum of consecutive naturals, for example, 16720897 + ... + 16720936.

It is an arithmetic number, because the mean of its divisors is an integer number (117046419).

Almost surely, 2^668836660 is an apocalyptic number.

It is an amenable number.

668836660 is an abundant number, since it is smaller than the sum of its proper divisors (735720368).

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

668836660 is a wasteful number, since it uses less digits than its factorization.

668836660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33441842 (or 33441840 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 49.

The square root of 668836660 is about 25861.8765753764. The cubic root of 668836660 is about 874.5272700898.

The spelling of 668836660 in words is "six hundred sixty-eight million, eight hundred thirty-six thousand, six hundred sixty".