My guess,
So based on this thread, Natasha Otomoski probably Satoshi Nakamoto, number 21 probably max supply of btc, based on coinmarketcap max btc supply is 21,000,000 which is have 21 too.
It is possible to turn the question into "Why Satoshi Nakamoto Create bitcoin with 21 million supply?", Its pretty similar tho, "Why The Comb Of Natasha Otomoski Has 21 Teeth?" , but idk, just guessing.
So based on this thread, Natasha Otomoski probably Satoshi Nakamoto, number 21 probably max supply of btc, based on coinmarketcap max btc supply is 21,000,000 which is have 21 too.
It is possible to turn the question into "Why Satoshi Nakamoto Create bitcoin with 21 million supply?", Its pretty similar tho, "Why The Comb Of Natasha Otomoski Has 21 Teeth?" , but idk, just guessing.
according to this reply I think answer should be in the Bitcoin Whitepaper or in Bitcoin source code.
1. I was searched the Whitepaper but couldn't find any clue, just a link to a ".txt" file in last page: http://www.weidai.com/bmoney.txt. I downloaded it and calculated its sha256 checksum (as private key) but it wasn't the correct answer.
2. therefore I was download the first version (0.1) of bitcoin source code that writhed by Satoshi Nakamoto. Satoshi sets total number of bitcoins to 21 million at line 680 of "main.cpp" file mathematically. above this line there is a comment writted by satoshi: "Subsidy is cut in half every 4 years" link: https://github.com/Maguines/Bitcoin-v0.1/blob/master/bitcoin0.1/src/main.cpp. if the question be about total number of bitcoins this comment is the answer. if we convert "4" to "four" the result has 32 character and 8 words! I was tested some different shapes of this comment but unfortunately couldn't find the correct answer.( a 32 character text could converted to 64 byte hex number that could be a private key) .
sorry for my bad English and if you find the answer according to my reply please donate me. I live in poverty and need money so much.
my bitcoin address: 112YeJTFugsuVswVDPzdQi2NTzBunhfVaS
interesting but i tried all combine (8!) doesnt work
good job
maybe it isn't the solution at all. or maybe it is just a part of solution and there be another parts. no one attention to that ".txt" at end of question, but I think that is a part of puzzle.