Nauru is about 25,141 times smaller than Yemen.

Yemen is approximately 527,968 sq km, while Nauru is approximately 21 sq km, making Nauru 0.0% the size of Yemen. Meanwhile, the population of Yemen is ~31.0 million people (31.0 million fewer people live in Nauru).
Tip: This to-scale comparison of Yemen vs. Nauru uses the Mercator projection, which distorts the size of regions near the poles.
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