You'll have to round each individual digit.
654,567 ---- 654,570 ---- 654,600 ---- 655,000
If this turns out to be incorrect then I believe the next logical step is to take 655,000 and round to 660,000. I'm almost completely positive that rounding past that number would be unreasonable and incorrect for the answer.
That should be the correct order. I haven't done rounding in the longest time but I'm pretty sure this is how you round numbers surpassing 2 digits.