Mongolia is the country with the lowest population density, there are just 5 people per square mile in Mongolia. By comparison, the USA has 80 people per square mile and Singapore has 16500!
I would have to say Mongolia. It has a population of 2.7 million, 1.5 million per square kms (land area), population density is 2 square kms, 604,249.63 square miles (land area).
