By Area - Russia
The largest country, by land mass is Russia, which is the biggest part of what was once U.S.S.R and it exists as a semi-presidential republic today. It covers more than a ninth of the Earth's total land mass. It covers a total area of 6,612,100 square miles (17,125,200 square kilometers), which constitutes about 11.5% of the Earth's total land mass.
The total land area on Earth is 197 million square miles or 510 million square kilometers. Situated in Eurasia, Russia extends across the whole of Northern part of Asia and about 40% of European land mass. It spans about 11 different time zones, with a variety of land forms and all kinds of climate conditions.
Russia has the world's biggest reserves of energy and minerals. It is still, unarguably, a superpower when it comes to energy resources. It also is fortunate enough to have the greatest forest reserves in the world, along with roughly 25% of the world's unfrozen freshwater reserves, in its lakes.
The country has the largest lake in the world, by volume, which is Baikal and it is also the deepest one in the world. Mount Elbrus, in Russia, is the highest topographical point in the whole of Europe. It also contains about 10% of the world's total arable land.
If one considers what really forms a country, is the people, then the largest one, by population, is China, that is the 'People's Republic of China', with a total population of 1,415,516,131 people and counting.