647638688 has 24 divisors (see below), whose sum is σ = 1275835680. Its totient is φ = 323616960.

The previous prime is 647638687. The next prime is 647638711. The reversal of 647638688 is 886836746.

It is a super-2 number, since 2×647638688² = 838871740388722688, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (647638687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54743 + ... + 65513.

It is an arithmetic number, because the mean of its divisors is an integer number (53159820).

Almost surely, 2^647638688 is an apocalyptic number.

It is an amenable number.

647638688 is a deficient number, since it is larger than the sum of its proper divisors (628196992).

647638688 is a wasteful number, since it uses less digits than its factorization.

647638688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12660 (or 12652 counting only the distinct ones).

The product of its digits is 9289728, while the sum is 56.

The square root of 647638688 is about 25448.7462952500. The cubic root of 647638688 is about 865.1888783083.

The spelling of 647638688 in words is "six hundred forty-seven million, six hundred thirty-eight thousand, six hundred eighty-eight".