6644646 has 16 divisors (see below), whose sum is σ = 14766000. Its totient is φ = 2214864.

The previous prime is 6644621. The next prime is 6644647. The reversal of 6644646 is 6464466.

It is a happy number.

6644646 is a `hidden beast` number, since 6 + 6 + 4 + 4 + 646 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 6644646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6644647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61471 + ... + 61578.

It is an arithmetic number, because the mean of its divisors is an integer number (922875).

Almost surely, 2^6644646 is an apocalyptic number.

6644646 is an abundant number, since it is smaller than the sum of its proper divisors (8121354).

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

6644646 is a wasteful number, since it uses less digits than its factorization.

6644646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123060 (or 123054 counting only the distinct ones).

The product of its digits is 82944, while the sum is 36.

The square root of 6644646 is about 2577.7210865414. The cubic root of 6644646 is about 187.9997547907. Note that the first 3 decimals are identical.

The spelling of 6644646 in words is "six million, six hundred forty-four thousand, six hundred forty-six".