Using English numbers (123) instead of Persian numbers (۱۲۳) in Persian layout

When I switch to Persian, the numbers are displayed as ۱۲۳. I want the numbers to be displayed as 123.

ubuntu 20.04

There are lots of environment variables for this kind of thing:

sh@balrog:~$ locale
LANG=en_US.UTF-8
LANGUAGE=en_US:en
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC=de_DE.UTF-8
LC_TIME=de_DE.UTF-8
LC_COLLATE="en_US.UTF-8"
LC_MONETARY=de_DE.UTF-8
LC_MESSAGES="en_US.UTF-8"
LC_PAPER=de_DE.UTF-8
LC_NAME=de_DE.UTF-8
LC_ADDRESS=de_DE.UTF-8
LC_TELEPHONE=de_DE.UTF-8
LC_MEASUREMENT=de_DE.UTF-8
LC_IDENTIFICATION=de_DE.UTF-8
LC_ALL=

In your case, LC_NUMERIC should do what you want:

export LC_NUMERIC=en_US.UTF-8

If that works (which I expect), put that line into your .bashrc file.