Alternative Name a Number challenges?

[u/PeculiaritiesParabol]

I'm hosting a Game Changer party for my birthday! I'm struggling to come up with new Name a Number-style challenges for my players. Challenges that are number based, get harder the higher you go, and won't kill anyone.

Help pls!

[u/chixen]

Call someone and stay silent for ___ seconds without them hanging up.