668140676 has 60 divisors (see below), whose sum is σ = 1384175772. Its totient is φ = 282127104.

The previous prime is 668140609. The next prime is 668140699. The reversal of 668140676 is 676041866.

It can be written as a sum of positive squares in 2 ways, for example, as 328696900 + 339443776 = 18130^2 + 18424^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 700616 + ... + 701568.

Almost surely, 2^668140676 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 668140676, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (692087886).

668140676 is an abundant number, since it is smaller than the sum of its proper divisors (716035096).

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

668140676 is an equidigital number, since it uses as much as digits as its factorization.

668140676 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1058 (or 1035 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 44.

The square root of 668140676 is about 25848.4172823018. The cubic root of 668140676 is about 874.2238236897.

The spelling of 668140676 in words is "six hundred sixty-eight million, one hundred forty thousand, six hundred seventy-six".