The number 6000 is already a whole number. A whole number is defined as a number without any fractional or decimal parts. In this case, 6000 fits that definition perfectly as it is a complete, unbroken number.
Whole numbers can include zero and all positive integers (1, 2, 3, …), and 6000 is simply a large whole number that indicates a quantity or count of something. For instance, if you have 6000 apples, it means you have exactly 6000 apples, with none missing or partially counted.