Final answer:
601 kg expressed as an integer remains 601 kg, since it is already a whole number and does not require any conversion.
Step-by-step explanation:
To express 601 kg as an integer, we do not need to apply any conversions, as 601 kg is already an integer value. The term 'integer' refers to a whole number that is not a fraction or a decimal. Therefore, 601 kg is an integer as it stands. It's important to note that when measuring mass or weight, it's beneficial to use units that keep the number manageable and avoid unnecessary complexity, as described with the examples of different weight measurements and their ease based on the unit used.