6646888672 has 24 divisors (see below), whose sum is σ = 13102739496. Its totient is φ = 3319208832.

The previous prime is 6646888669. The next prime is 6646888681. The reversal of 6646888672 is 2768886466.

It is a super-2 number, since 2×6646888672² = 88362258035923847168, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 6646888672.

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, 106783 + ... + 157150.

It is an arithmetic number, because the mean of its divisors is an integer number (545947479).

Almost surely, 2^6646888672 is an apocalyptic number.

It is an amenable number.

6646888672 is a deficient number, since it is larger than the sum of its proper divisors (6455850824).

6646888672 is a wasteful number, since it uses less digits than its factorization.

6646888672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264730 (or 264722 counting only the distinct ones).

The product of its digits is 37158912, while the sum is 61.

The square root of 6646888672 is about 81528.4531436725. The cubic root of 6646888672 is about 1880.2090336456.

The spelling of 6646888672 in words is "six billion, six hundred forty-six million, eight hundred eighty-eight thousand, six hundred seventy-two".