6643624 has 32 divisors (see below), whose sum is σ = 13547520. Its totient is φ = 3036096.

The previous prime is 6643607. The next prime is 6643633. The reversal of 6643624 is 4263466.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 12957 + ... + 13459.

It is an arithmetic number, because the mean of its divisors is an integer number (423360).

Almost surely, 2^6643624 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 6643624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6773760).

6643624 is an abundant number, since it is smaller than the sum of its proper divisors (6903896).

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

6643624 is a wasteful number, since it uses less digits than its factorization.

6643624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649 (or 645 counting only the distinct ones).

The product of its digits is 20736, while the sum is 31.

The square root of 6643624 is about 2577.5228417999. The cubic root of 6643624 is about 187.9901156717.

The spelling of 6643624 in words is "six million, six hundred forty-three thousand, six hundred twenty-four".