Mali is 34% larger than Nigeria.
Area: 1,240,192 km2 World Factbook
Population: 16,455,903 (July 2014) World Factbook
Mali, officially the Republic of Mali, is a landlocked country in West Africa. Mali is bordered by Algeria to the north, Niger to the east, Burkina Faso and Ivory Coast to the south, Guinea to the south-west, and Senegal and Mauritania to the west. Wikipedia
Area: 923,768 km2 World Factbook
Population: 177,155,754 (July 2014) World Factbook
Nigeria, officially the Federal Republic of Nigeria, is a federal constitutional republic comprising 36 states and its Federal Capital Territory, Abuja. Wikipedia