668678660 has 48 divisors (see below), whose sum is σ = 1515141936. Its totient is φ = 246423552.

The previous prime is 668678641. The next prime is 668678669. The reversal of 668678660 is 66876866.

668678660 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 181063936 + 487614724 = 13456^2 + 22082^2 .

It is not an unprimeable number, because it can be changed into a prime (668678669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 152012 + ... + 156348.

It is an arithmetic number, because the mean of its divisors is an integer number (31565457).

Almost surely, 2^668678660 is an apocalyptic number.

It is an amenable number.

668678660 is an abundant number, since it is smaller than the sum of its proper divisors (846463276).

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

668678660 is a wasteful number, since it uses less digits than its factorization.

668678660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4952 (or 4950 counting only the distinct ones).

The product of its (nonzero) digits is 3483648, while the sum is 53.

The square root of 668678660 is about 25858.8217055611. The cubic root of 668678660 is about 874.4584011622.

The spelling of 668678660 in words is "six hundred sixty-eight million, six hundred seventy-eight thousand, six hundred sixty".