The release format can be one of the following:
An album (LP)
Generally speaking, the number of tracks on your release is what distinguishes its format.
Single: 1-3 tracks
EP: 4-6 tracks
Album: 7 or more tracks
It is important to note that format definitions can vary from service to service so although it is tagged as a single in our service, you might see something different when you look at Apple Music.