Japan is 27 times larger than Puerto Rico.
Area: 377,915 km2 World Factbook
Population: 127,103,388 (July 2014) World Factbook
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south. Wikipedia
Area: 13,790 km2 World Factbook
Population: 3,620,897 (July 2014) World Factbook
Puerto Rico, officially the Commonwealth of Puerto Rico, is an unincorporated territory of the United States, located in the northeastern Caribbean east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands. Wikipedia