Put it all into a savings account and spend it wisely as needs present themselves.
Buy a few things right away. Maybe a new car, a boat, a house, etc. The rest I'll put away for a rainy day.
Spend it all on something really big and eccentric. You can't take it with you right?
Donate it to the sick, injured, and poor.
Donate it to science, research, and development.
Invest it into the market. You'll soon have even more!