6644688 has 60 divisors (see below), whose sum is σ = 18272640. Its totient is φ = 2080256.

The previous prime is 6644681. The next prime is 6644717. The reversal of 6644688 is 8864466.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6644681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13633 + ... + 14111.

It is an arithmetic number, because the mean of its divisors is an integer number (304544).

Almost surely, 2^6644688 is an apocalyptic number.

6644688 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6644688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9136320).

6644688 is an abundant number, since it is smaller than the sum of its proper divisors (11627952).

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

6644688 is a wasteful number, since it uses less digits than its factorization.

6644688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 524 (or 501 counting only the distinct ones).

The product of its digits is 221184, while the sum is 42.

The square root of 6644688 is about 2577.7292332594. The cubic root of 6644688 is about 188.0001508977. Note that the first 3 decimals are identical.

The spelling of 6644688 in words is "six million, six hundred forty-four thousand, six hundred eighty-eight".