3 is my 11 year old grandson’s favorite number.
I’m unsure exactly why.
Maybe because it’s because it’s a prime number.
I recall reading the 2003 Mark Haddon mystery novel “The Curious Incident of the Dog in the Night-time” and being struck by how the various chapters were all numbered prime numbers.
Any book like that couldn’t be all bad.
And it wasn’t.
But there are other prime numbers, and they’re not favorites.