Indonesia dwarfs South America: about 1,872,242 km² km² against 17,840,000 km² km². At true size Indonesia is about 9.5× larger — the whole of South America fits into Indonesia roughly 9 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 9× into South America.