The address of the building is literally Princeton within city limits (according to Google Maps). Ewing is a bit too far. You might be thinking of the data center, though to be quite honest I don't remember where it is.
Though it has a Princeton address, the offices are really within the Montgomery city limits.
Princeton has an enormous mailing address area, though I have no idea how it got to be so. I grew up in the area and it sometimes felt like Princeton and Trenton were the only two mailing addresses in all of Mercer county