Guyana is about 16 times bigger than Montenegro.

Montenegro is approximately 13,812 sq km, while Guyana is approximately 214,969 sq km, making Guyana 1,456% larger than Montenegro. Meanwhile, the population of Montenegro is ~623,129 people (212,857 more people live in Guyana).
Tip: This to-scale comparison of Montenegro vs. Guyana uses the Mercator projection, which distorts the size of regions near the poles.
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