I think they are called stink bugs. They hibernate in the walls in winter. And they crawl out inside the house at times- a few times a year, usually in November, December. I guess they're old bugs, because they are super easy to swat.
BTW. one of the things about NYC, it doesn't matter where you live- in a luxury tower or basement apt- you either have roaches or mice. It's one or the other. If you don't have roaches, it's because the mice ate 'em. If you think mice and roaches can't get up to the 121st floor, you haven't lived in NYC.