6640640006 has 64 divisors (see below), whose sum is σ = 13410109440. Its totient is φ = 2381823360.

The previous prime is 6640640003. The next prime is 6640640021. The reversal of 6640640006 is 6000460466.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6640640003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 774515 + ... + 783041.

It is an arithmetic number, because the mean of its divisors is an integer number (209532960).

Almost surely, 2^6640640006 is an apocalyptic number.

6640640006 is an abundant number, since it is smaller than the sum of its proper divisors (6769469434).

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

6640640006 is a wasteful number, since it uses less digits than its factorization.

6640640006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8949.

The product of its (nonzero) digits is 20736, while the sum is 32.

The square root of 6640640006 is about 81490.1221375941. The cubic root of 6640640006 is about 1879.6196610632.

It can be divided in two parts, 6640 and 640006, that added together give a palindrome (646646).

The spelling of 6640640006 in words is "six billion, six hundred forty million, six hundred forty thousand, six".