6643105780 has 12 divisors (see below), whose sum is σ = 13950522180. Its totient is φ = 2657242304.

The previous prime is 6643105771. The next prime is 6643105787. The reversal of 6643105780 is 875013466.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 3198354916 + 3444750864 = 56554^2 + 58692^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6643105787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166077625 + ... + 166077664.

It is an arithmetic number, because the mean of its divisors is an integer number (1162543515).

Almost surely, 2^6643105780 is an apocalyptic number.

It is an amenable number.

6643105780 is an abundant number, since it is smaller than the sum of its proper divisors (7307416400).

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

6643105780 is a wasteful number, since it uses less digits than its factorization.

6643105780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332155298 (or 332155296 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 6643105780 is about 81505.2500149530. The cubic root of 6643105780 is about 1879.8522763812.

The spelling of 6643105780 in words is "six billion, six hundred forty-three million, one hundred five thousand, seven hundred eighty".