Hello @Kenyon_Hackett
Just use some basic functions with your variable.
{{replace(+123456789; "+"; emptystring)}}
https://www.make.com/en/help/functions/string-functions#replace--text--search-string--replacement-string-
For more knowledge:
I recommend that you check out the official free course at Make Academy. It’s worth it if you want to learn more about Make in detail.