Answer: whole note
A whole note is four beats long, and a quarter note is one beat long. If you play four quarter notes, it’ll be the same amount of time as a whole note.
Keep in mind that these are the note values:
Thirty second note: 1/8th beat of a quarter note
Sixteenth note: 1/4th beat of a quarter note
Eighth note: half beat of a quarter note
Quarter note: one beat long
Dotted quarter note: about two beats long
Half note: two beats long
Dotted half note: three beats long
Whole note: four beats long