6645356800 has 54 divisors (see below), whose sum is σ = 16448312258. Its totient is φ = 2658140160.

The previous prime is 6645356779. The next prime is 6645356803. The reversal of 6645356800 is 86535466.

It can be written as a sum of positive squares in 3 ways, for example, as 265820416 + 6379536384 = 16304^2 + 79872^2 .

It is not an unprimeable number, because it can be changed into a prime (6645356803) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 512769 + ... + 525568.

Almost surely, 2^6645356800 is an apocalyptic number.

It is an amenable number.

6645356800 is an abundant number, since it is smaller than the sum of its proper divisors (9802955458).

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

6645356800 is a wasteful number, since it uses less digits than its factorization.

6645356800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1038363 (or 1038344 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 43.

The square root of 6645356800 is about 81519.0578944580. The cubic root of 6645356800 is about 1880.0645820579.

The spelling of 6645356800 in words is "six billion, six hundred forty-five million, three hundred fifty-six thousand, eight hundred".