Well the replies in this thread are kinda the same and most are telling you you can't double it SAFELY, double yes safely no I agree with this. Now if you are willing to take risks you could invest after doing research but you would probably want help of a professional as well if it's about this big of a sum
there are actually safe ways of doubling it, you can invest it into bitcoins and then just wait a long time, sooner or later it will happen