I call it 441 because I have a little OCD and the "1" is a vertical number and 441 generally goes North-South or South-North. Also, back in Ohio we had a main N-S road that was called 741. If I am giving directions through Leesburg after the "split" I will say "then continue on 27."

I just remembered something. US Highways are even-numbered East-West & odd-numbered N-S aren't they?