6644556644 has 24 divisors (see below), whose sum is σ = 13027905408. Its totient is φ = 2938623840.

The previous prime is 6644556619. The next prime is 6644556673. The reversal of 6644556644 is 4466554466.

It is a zygodrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 6644556592 and 6644556601.

It is an unprimeable number.

It is an upside-down number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2039084 + ... + 2042339.

It is an arithmetic number, because the mean of its divisors is an integer number (542829392).

Almost surely, 2^6644556644 is an apocalyptic number.

It is an amenable number.

6644556644 is a deficient number, since it is larger than the sum of its proper divisors (6383348764).

6644556644 is a wasteful number, since it uses less digits than its factorization.

6644556644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4081475 (or 4081473 counting only the distinct ones).

The product of its digits is 8294400, while the sum is 50.

The square root of 6644556644 is about 81514.1499618318. The cubic root of 6644556644 is about 1879.9891205799.

The spelling of 6644556644 in words is "six billion, six hundred forty-four million, five hundred fifty-six thousand, six hundred forty-four".