The number 7 is seen as lucky in slots and pop culture because it often...

https://www.last-bookmarks.win/the-number-7-is-seen-as-lucky-in-slots-and-pop-culture-because-it-often

The number 7 is seen as lucky in slots and pop culture because it often symbolizes good fortune and completeness, like the seven-day week. In classic slot machines, hitting triple 7s (777) usually means a big win