Armenia is about 2.1 times bigger than Montenegro.

Montenegro is approximately 13,812 sq km, while Armenia is approximately 29,743 sq km, making Armenia 115% larger than Montenegro. Meanwhile, the population of Montenegro is ~604,966 people (2.4 million more people live in Armenia).
Tip: This to-scale comparison of Montenegro vs. Armenia uses the Mercator projection, which distorts the size of regions near the poles.
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