I would be set for the rest of my life if I got half a mill falling from sky today, I guess I could even make it work with 250k.
Currently I am pondering how absurd amount of money a billion of dollars is. When loads of people can only -earn and eat through/spend not save- $1 million; working their asses off for something like 20 years.
If you are interested, the /r/fire and /r/financialindependence subreddits are useful.
Maybe you only have a few years left to live? If not, I’m not sure where one can live on $10,000 to $15,000 a year and pay for shelter, food, clothing, and healthcare. It costs more than that per year for health insurance for one adult over 40 in the US.
That is what $500k grants you, chop those in half for $250k.
You may enjoy reading Brewster’s Millions, or watching one of the many movie adaptations made over the years.