2128812644 has 36 divisors (see below), whose sum is σ = 4336371900. Its totient is φ = 911776320.

The previous prime is 2128812643. The next prime is 2128812671. The reversal of 2128812644 is 4462188212.

It can be written as a sum of positive squares in 2 ways, for example, as 2017087744 + 111724900 = 44912^2 + 10570^2 .

It is a junction number, because it is equal to n+sod(n) for n = 2128812598 and 2128812607.

It is not an unprimeable number, because it can be changed into a prime (2128812643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 497474 + ... + 501734.

It is an arithmetic number, because the mean of its divisors is an integer number (120454775).

Almost surely, 2^2128812644 is an apocalyptic number.

It is an amenable number.

2128812644 is an abundant number, since it is smaller than the sum of its proper divisors (2207559256).

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

2128812644 is a wasteful number, since it uses less digits than its factorization.

2128812644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6828 (or 6819 counting only the distinct ones).

The product of its digits is 49152, while the sum is 38.

The square root of 2128812644 is about 46139.0576843524. The cubic root of 2128812644 is about 1286.4092285949.

The spelling of 2128812644 in words is "two billion, one hundred twenty-eight million, eight hundred twelve thousand, six hundred forty-four".