Tajikistan is 3.7 times larger than Bhutan.
Area: 38,394 km2 World Factbook
Population: 733,643 (July 2014) World Factbook
Bhutan, officially the Kingdom of Bhutan, is a landlocked country in South Asia located at the eastern end of the Himalayas. It is bordered to the north by China and to the south, east and west by India. Wikipedia
Area: 143,100 km2 World Factbook
Population: 8,051,512 (July 2014) World Factbook
Tajikistan, officially the Republic of Tajikistan, is a mountainous landlocked country in Central Asia. It is bordered by Afghanistan to the south, Uzbekistan to the west, Kyrgyzstan to the north, and China to the east. Mountains cover more than 90% of the country. Wikipedia