Bulgaria is about 2.8 times smaller than Oman.

Oman is approximately 309,500 sq km, while Bulgaria is approximately 110,879 sq km, making Bulgaria 35.83% the size of Oman. Meanwhile, the population of Oman is ~5.5 million people (938,611 more people live in Bulgaria).
Tip: This to-scale comparison of Oman vs. Bulgaria uses the Mercator projection, which distorts the size of regions near the poles.
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