The Majapahit Empire wasn't really massive as you might think normally. The territory they controlled was rather small, basically the eastern half of Java and also Bali. What they had, which made them seemingly big, were actually Tributaries. They were technically still their own countries, with the caveat that they had to pay tribute to Majapahit.

According to the Nagarakretagama, written in honour of king Hayam Wuruk, during whom Majapahit peaked, they had a whopping 98 Tributaries, plus they controlled the vital Trade Routes for spices of the eastern Spice Islands, for example Nutmeg.