I'd talk to a group of professionals. Start with an attorney, CPA and financial guru. The reason you talk to all is for all the ends and outs of what could happen with your money and the income received. Some things are tax-deferred, tax free and other hold liability that you may not have the stomach for long term.
Mix things up. Old saying that I will let you finish is "Don't put all your eggs......."
Since I am in real estate I am partial to multi-family properties and commercial for long-term appreciation as well as good income potential.
Start-up companies are high risk, but have big rewards.
Stock, bonds and mutual funds. You could add a little day trading for fun.
Do remember one thing when doing anything. If you own an asset it has to be maintained and constantly monitored. If you are not in a position to do that then hire a professional.
I believe less is more when it comes to investing. I'd rather have one or two big properties than 30 scattered all over town.
At the end of the day with 5 million you can pretty much do anything. If you like Jersey Mikes you could open your own franchise and eat there daily lol.
Buy a franchise that doesn't require owner participation, but has returns of 6% to 15%.
If you like the DFW area I can show you some good income producing properties that you will receive a good income as well as have good appreciation.
One final thing is to take a little of that money and enjoy a nice vacation to New Zealand for a full month. Just make sure you go in the summer which is reversed from the US. Consider investing there and other foreign countries to have assets in additional countries just in case the petro dollar drops at some time here.