6646344768 has 168 divisors, whose sum is σ = 21825744512. Its totient is φ = 1894275072.

The previous prime is 6646344767. The next prime is 6646344773. The reversal of 6646344768 is 8674436466.

It is a tau number, because it is divible by the number of its divisors (168).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (6646344763) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1840821 + ... + 1844427.

Almost surely, 2^6646344768 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 6646344768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10912872256).

6646344768 is an abundant number, since it is smaller than the sum of its proper divisors (15179399744).

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

6646344768 is a wasteful number, since it uses less digits than its factorization.

6646344768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4089 (or 4076 counting only the distinct ones).

The product of its digits is 13934592, while the sum is 54.

The square root of 6646344768 is about 81525.1174056192. The cubic root of 6646344768 is about 1880.1577474393.

The spelling of 6646344768 in words is "six billion, six hundred forty-six million, three hundred forty-four thousand, seven hundred sixty-eight".