That's actually a real phone number, in this case, the Hotel Pennsylvania, just across 7th Avenue from Penn Station in Manhattan. It's the longest-serving phone number in New York, and it's about to be replaced. It was the home to a number of great swing bands in its day, and Glenn Miller, apparently hard up for inspiration, used the phone number.
Both the hotel and the original train station were built by the Pennsylvania Railroad. If you follow the link to destruction, they'll tell you it opened with 2200 rooms in 1919, and was designed by McKim, Mead, and White. It used to be one of the great New York hotels, being at one time or another part of the great Statler chain, eventually bought out by Hilton. After passing through bankruptcy, it later re-emerged as the Hotel Pennsylvania. It was one of the fine hotels just pre-Art Deco, but flexible enough to be deco-ed up by the chandelier and the artwork in the lobby. By the time I stayed there - twice - it was already fading, and now it's considered "discount," a dangerous status for a building with that kind of location. There's a plan to the lobby, but not to the main floor, and the shops are all different, crammed in like different tenants on a old strip mall. Each has its own flavor, but together they're a mishmosh.
I did stay there when I was in grade school and then again in high school. Each time it was for a school trip to the UN - once to the real thing, once to a convention dedicated to our recreating it to show how important and effective it was. Bleh. Now, what I remember most about the trip was a detour, courtesy of my Dad, to a deli near Lincoln Center where they loaded me up with the Dagwood Bumstead Special for about $1.50.
There's something seriously wrong with an educational system taht idolizes international bureaucrats and ignores great architecture.