So Storm_Epidemic, your are saying that the map is exactly 16384 x 16384 square meters. From of the proof of that Russia is 4096 x 4096 square meters, and medium would be 2048 x 2048.

Insane Map size = 16384 x 16384
Large Map size = 4096 x 4096
Medium Map size = 2048 x 2048
Small Map size = 1024 x 1024