Execute the command prompt "command not found" in shell

definition of shell:

-sharp!/bin/bash

res=`2222222222 | md5sum | cut -d " " -f1`

echo "res: " ${res}

write in a file and run the result as follows:

./sh-test.sh: line 3: 2222222222: command not found
res:  d41d8cd98f00b204e9800998ecf8427e

I"d like to ask why you prompted command not found?.

Mar.20,2021

-sharp!/bin/bash

res=`echo 2222222222 | md5sum | cut -d ' ' -f1`

echo "res: " ${res}

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