Sector 21538

From Memory Alpha, the free Star Trek reference.

Sector 21538 is a sector in or near Federation space.

A Starship Mission Status readout of status of several Federation starships' missions for Sector 21538 up to 23079 was often displayed on viewscreens aboard starship USS Enterprise-D during the 2360s. (Star Trek: The Next Generation set decoration)

Sector 21538 was not mentioned on screen, but rather was seen on a viewscreen chart on observation lounge and bridge computer stations. It was also displayed on a PADD, as shown in the It's A Wrap! sale and auction (item #4273).