US 500 is just a number that lets you track performance of the instruments comprising the index, so you can't invest in it directly. But you can buy US 500 futures or funds or invest in its components.
The lowest ever quote of US 500 is 1833.6 USD. It was reached on Feb 12, 2016.
US 500 reached its highest quote on Apr 1, 2024 — 5276.4 USD.