The Doctor and Yaz in “The Tsuranga Conundrum”

Pick a number between 1 and 100.

51.

Pentagonal number. Interesting. [She sonics a bomb] Get in that corner.

What was the number for?

Number of seconds before the bomb goes off. I moved it forward a bit.

What?! I would've gone higher!

Good number, 51! Atomic number of antimony. Number of Federalist Papers written by Alexander Hamilton. I love that show, I've seen all 900 casts.