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

https://marcossmartchat.image-perth.org/why-do-lists-and-stories-love-the-number-7

The number 7 is seen as lucky in slots and pop culture because it often represents good fortune and completeness, like the seven-day week. Classic slot machines feature the 777 combo, which is a top prize symbol