Bronstein/Semendjajew’s Handbook of Mathematics[0] is something close to what you envision. It’s helpful if you just need to look up a given formulae and understand the larger picture, but it will be incomprehensible if you don’t know at least some maths. Note that the HHGTG, while giving you some information about planets, will be useless unless you know something about hitchhiking, too: Like the Bronstein, it gives you bits and pieces to remember parts of the larger picture, but it doesn’t give the larger picture to you.