At true size, Russia is about 9.1× the size of Sudan. On the old 1569 Mercator map the same two appear about 50.8× apart — the old map exaggerates their difference by a factor of 5.6×.
It is a latitude illusion: Russia sits near 66°, where Mercator multiplies area by about 6.1×, while Sudan lies near 16°, inflated only about 1.1×. Equal Earth removes that latitude tax, and the pair settles at its honest 9.1×.