Mauritania is about 21,035 times bigger than Bouvet Island.

Bouvet Island is approximately 49 sq km, while Mauritania is approximately 1,030,700 sq km, making Mauritania 2,103,369% larger than Bouvet Island.
Tip: This to-scale comparison of Bouvet Island vs. Mauritania uses the Mercator projection, which distorts the size of regions near the poles.