The number 7 is lucky in slots and pop culture because it’s tied to positive...

https://research-wiki.win/index.php/Why_Do_People_Call_Seven_a_Lucky_Number_but_Admit_It_Is_Not_Real%3F

The number 7 is lucky in slots and pop culture because it’s tied to positive ideas like the seven-day week and good fortune. In classic slot games, hitting 777 often means a big win