Apk Double the size of the report from Editor Log

My exported Apk of my game is 8.72 mb which is huge for the small game I've made. I al really do understand why, since the editor log says it should be 4.1 mb, as shown below.

Textures 1.2 mb 30.0%

Meshes 0.0 kb 0.0%

Animations 0.0 kb 0.0%

Sounds 5.7 kb 0.1%

Shaders 0.0 kb 0.0%

Other Assets 27.8 kb 0.7%

Levels 11.8 kb 0.3%

Scripts 78.6 kb 1.9%

Included DLLs 2.6 mb 63.6%

File headers 148.2 kb 3.5%

Complete size 4.1 mb 100.0%

Another question of mine is, almost 64% of the game size, is because of the Dlls unity uses. Is there a way to minimize the size of this?