Yes, it is encrypted. When you run a Monero node it's using 'pedersen commitments' to validate that all inputs/outputs for every transaction on the blockchain "cancel out" (no Monero is being created from thin air) but without knowing the actual values for any specific transaction.
https://www.getmonero.org/resources/moneropedia/pedersen-commitment.html
Another cool thing about pedersen commitments is that they are "perfectly hiding" meaning it's impossible to break it's privacy even for a quantum computer
"Perfectly binding or hiding means that even with infinite computing power it would be impossible to break the property (bindingness/hidingness)."
https://docs.grin.mw/wiki/miscellaneous/switch-commitments/#properties-of-commitment-schemes
