Japan is 1,040 times larger than Las Vegas.
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: 363 km2 calculated
Las Vegas, officially the City of Las Vegas and often known as simply Vegas, is the most populous city in the state of Nevada and the county seat of Clark County. Wikipedia