一、全球人口密度最高的是澳门，每平方公里住了２１９６１人，密度最低的是丹麦的格陵兰岛，每平方公里仅０．１６人。二、全球平均寿命最长的是日本，超过８０岁；最短的塞拉利昂，仅３７岁。三、全球经济规模最大的国家是美国，国内生产总值已达７８３４０亿美元；最小的是 First, the world’s population density is highest in Macao, living 21,961 people per square kilometer, the lowest density is Denmark’s Greenland, only 0.16 people per square kilometer. Second, the longest average life expectancy in the world is Japan, over 80 years old; the shortest Sierra Leone, only 37 years old. Third, the largest country in the global economy is the United States, with a GDP of 78.34 billion U.S. dollars. The smallest is