Asia dwarfs Indonesia: about 44,580,000 km² km² against 1,872,242 km² km². At true size Asia is about 23.8× larger — the whole of Indonesia fits into Asia roughly 23 times.
The old Mercator map treated both about equally (1× vs 1× inflation), so at least their relative sizes were preserved — even if both were drawn at the wrong absolute scale.
Indonesia fits 23× into Asia.