The figure I’m seeing is approximately 18 million. So 1 million barrels would meet our demands for a little over an hour.
BTW, I got that figure from this 2021 Breitbart article.
https://www.breitbart.com/politics/2021/11/25/flashback-democrats-cut-trumps-replenishment-of-oil-reserve-when-prices-were-cheap-strike-a-blow-to-big-oil/
The lower figure is for gasoline only.