2128556866664 has 16 divisors (see below), whose sum is σ = 3991198958820. Its totient is φ = 1064237144320.

The previous prime is 2128556866621. The next prime is 2128556866717. The reversal of 2128556866664 is 4666686558212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 2096964648100 + 31592218564 = 1448090^2 + 177742^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 2128556866664.

It is an unprimeable number.

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, 4941479 + ... + 5354934.

Almost surely, 2^{2128556866664} is an apocalyptic number.

It is an amenable number.

2128556866664 is a deficient number, since it is larger than the sum of its proper divisors (1862642092156).

2128556866664 is a wasteful number, since it uses less digits than its factorization.

2128556866664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10322260 (or 10322256 counting only the distinct ones).

The product of its digits is 199065600, while the sum is 65.

The spelling of 2128556866664 in words is "two trillion, one hundred twenty-eight billion, five hundred fifty-six million, eight hundred sixty-six thousand, six hundred sixty-four".