6644939 has 8 divisors (see below), whose sum is σ = 7749600. Its totient is φ = 5695368.

The previous prime is 6644933. The next prime is 6644959. The reversal of 6644939 is 9394466.

It is a de Polignac number, because none of the positive numbers 2^k-6644939 is a prime.

It is a d-powerful number, because it can be written as 6 + 6⁸ + 4⁵ + 4⁶ + 9² + 3¹¹ + 9⁷ .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6644896 and 6644905.

It is not an unprimeable number, because it can be changed into a prime (6644933) 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, 9344 + ... + 10029.

It is an arithmetic number, because the mean of its divisors is an integer number (968700).

Almost surely, 2^6644939 is an apocalyptic number.

6644939 is a deficient number, since it is larger than the sum of its proper divisors (1104661).

6644939 is an equidigital number, since it uses as much as digits as its factorization.

6644939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19394 (or 19380 counting only the distinct ones).

The product of its digits is 139968, while the sum is 41.

The square root of 6644939 is about 2577.7779190613. Note that the first 3 decimals coincide. The cubic root of 6644939 is about 188.0025180740.

The spelling of 6644939 in words is "six million, six hundred forty-four thousand, nine hundred thirty-nine".