  A positive integer $n$ is said to be a Zumkeller number or an integer-perfect
number if the set of its positive divisors can be partitioned into two subsets
of equal sums. In this paper, we prove several results regarding Zumkeller
numbers. For any positive integer $m$, we prove that there are infinitely many
positive integers $n$ for which $n+1,\cdots, n+m$ are all Zumkeller numbers.
Additionally, we show that every positive integer greater than $94185$ can be
expressed as a sum of two Zumkeller numbers and that all sufficiently large
integers can be written as a sum of a Zumkeller number and a practical number.
We also show that there are infinitely many positive integers that cannot be
expressed as a sum of a Zumkeller number and a square or a prime.
