6643560 has 128 divisors (see below), whose sum is σ = 24883200. Its totient is φ = 1378560.

The previous prime is 6643537. The next prime is 6643589. The reversal of 6643560 is 653466.

It is a Harshad number since it is a multiple of its sum of digits (30).

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 31 ways as a sum of consecutive naturals, for example, 8881 + ... + 9599.

It is an arithmetic number, because the mean of its divisors is an integer number (194400).

Almost surely, 2^6643560 is an apocalyptic number.

6643560 is a gapful number since it is divisible by the number (60) 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 6643560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12441600).

6643560 is an abundant number, since it is smaller than the sum of its proper divisors (18239640).

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

6643560 is a wasteful number, since it uses less digits than its factorization.

6643560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 751 (or 747 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 30.

The square root of 6643560 is about 2577.5104267490. The cubic root of 6643560 is about 187.9895120149.

It can be divided in two parts, 664 and 3560, that added together give a palindrome (4224).

The spelling of 6643560 in words is "six million, six hundred forty-three thousand, five hundred sixty".