321. An Easy Riddle That is Also a Wheel

RIDDLE 321:

I keep things together, and have a silent drop, I’m a secret number that people forget a lot. When I’m up, I’m on display, and as a ball, I’m fun to play; what word am I?

Look for clues in the title, background photo, and tags (tags are below).

Listen to the Video Riddle Featuring Multiple-Choice Answers:

ANSWER IS HERE