6644786680 has 128 divisors (see below), whose sum is σ = 17540167680. Its totient is φ = 2218245120.

The previous prime is 6644786671. The next prime is 6644786683. The reversal of 6644786680 is 866874466.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6644786683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2775564 + ... + 2777956.

It is an arithmetic number, because the mean of its divisors is an integer number (137032560).

Almost surely, 2^6644786680 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6644786680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8770083840).

6644786680 is an abundant number, since it is smaller than the sum of its proper divisors (10895381000).

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

6644786680 is a wasteful number, since it uses less digits than its factorization.

6644786680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2669 (or 2665 counting only the distinct ones).

The product of its (nonzero) digits is 9289728, while the sum is 55.

The square root of 6644786680 is about 81515.5609684433. The cubic root of 6644786680 is about 1880.0108155406.

It can be divided in two parts, 6644786 and 680, that added together give a palindrome (6645466).

The spelling of 6644786680 in words is "six billion, six hundred forty-four million, seven hundred eighty-six thousand, six hundred eighty".