As @quid says, there's no absolute upper bound. If you are smart or lucky enough to make just the right investments, you could make 1000% profit every day or more. Well, I suppose someone could come up with "real world" upper bounds. If after 10 days you own all the wealth in the world, you're pretty much done, unless you can figure out ways to dramatically increase the world's total wealth.
But two things to bear in mind:
(a) Every investment has potential for gain, but also risk of loss. What if you invested this million dollars and lost money, and then the bank comes asking for their money back? You'd presumably have to make up the difference.
(b) Even if you did make money, I'd question if you would be allowed to keep it.
I read a story in the news years ago that the IRS made a mistake and sent a taxpayer a refund check for, I forget the numbers, but he was supposed to get a few hundred dollars and instead they sent him tens of millions. He got the clever idea that he would deposit the check in an interest-bearing account, then promptly contact the IRS so there was no question that he was trying to keep the money. He hoped that it would take a long time for the bureaucratic wheels to grind and for the IRS to tell him to pay the money back and to tell him what mechanics to go through to do that, who to write the check to and where to send it or whatever. In the mean time he'd collect the interest on tens of millions of dollars.
Nice try, but the IRS demanded he pay back the money with interest. He didn't get to keep any of it.