Australia is about 4.2 times bigger than Sudan.

Sudan is approximately 1,861,484 sq km, while Australia is approximately 7,741,220 sq km, making Australia 316% larger than Sudan. Meanwhile, the population of Sudan is ~51.7 million people (24.0 million fewer people live in Australia).
Tip: This to-scale comparison of Sudan vs. Australia uses the Mercator projection, which distorts the size of regions near the poles.
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