6668025640 has 32 divisors (see below), whose sum is σ = 15112581480. Its totient is φ = 2647739392.

The previous prime is 6668025619. The next prime is 6668025649. The reversal of 6668025640 is 465208666.

It can be written as a sum of positive squares in 4 ways, for example, as 5304791556 + 1363234084 = 72834^2 + 36922^2 .

It is not an unprimeable number, because it can be changed into a prime (6668025649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 602917 + ... + 613876.

Almost surely, 2^6668025640 is an apocalyptic number.

It is an amenable number.

6668025640 is an abundant number, since it is smaller than the sum of its proper divisors (8444555840).

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

6668025640 is a wasteful number, since it uses less digits than its factorization.

6668025640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1216941 (or 1216937 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 43.

The square root of 6668025640 is about 81657.9796468171. The cubic root of 6668025640 is about 1882.1999333604.

The spelling of 6668025640 in words is "six billion, six hundred sixty-eight million, twenty-five thousand, six hundred forty".