I would invest this in a diversified portfolio of low-cost mutual funds at Vanguard and/or Fidelity.
BUT, that’s not the real end of the story! Here’s what I would really do in your shoes.
1. Consult my estate planning attorney, make sure I have an updated Revocable Living Trust, and open any new accounts in the name of the RLT.
2. Consider grandchildren — if you already have them — and invest in a 529 College Savings Plan for EACH of them. You can give $17,000 a year (each) OR combine 5 years of the allowable gift into one huge contribution and full fund their college educations. Read this: https://www.terrysavage.com/529-plans-even-better-now-2/
3. Meet with a fee-only FIDUCIARY financial planner to consider your own plan in light of this new money.
Read this article.
In the meantime, I would put the money in T-bills. Read this: https://www.terrysavage.com/t-bills-beat-cds/