6644561 has 8 divisors (see below), whose sum is σ = 8284224. Its totient is φ = 5177520.

The previous prime is 6644551. The next prime is 6644579. The reversal of 6644561 is 1654466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6644561 - 2¹⁰ = 6643537 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6644551) 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 7 ways as a sum of consecutive naturals, for example, 43070 + ... + 43223.

It is an arithmetic number, because the mean of its divisors is an integer number (1035528).

Almost surely, 2^6644561 is an apocalyptic number.

It is an amenable number.

6644561 is a deficient number, since it is larger than the sum of its proper divisors (1639663).

6644561 is a wasteful number, since it uses less digits than its factorization.

6644561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86311.

The product of its digits is 17280, while the sum is 32.

The square root of 6644561 is about 2577.7045990571. The cubic root of 6644561 is about 187.9989531404.

It can be divided in two parts, 664 and 4561, that added together give a palindrome (5225).

The spelling of 6644561 in words is "six million, six hundred forty-four thousand, five hundred sixty-one".