1 million allegedly mined by Satoshi
3 to 4 million lost over the years.
About 5 million not moving. I'm sure there's a site out there that can just look a coins that have not moved in over 7 or 8 years, and you have a good idea of coins that are lost, gone, forgotten, or otherwise inaccessible.
Not exactly this but I like to see the list of the richiest bitcoin wallets of all time.
Other than exchanges and big unknown wallets, there is a lot of old wallets with hundreds or thousands of coins lost in there or maybe just waiting for a big pump!
https://bitinfocharts.com/top-100-richest-bitcoin-addresses.htmlThe top 21 has 31k btc and the last movement was in 2010
And others never sent anything. Top 54 to 69 has 12k btc each and never saw movements.