Simple calc
This bomb can turn Coney Island into a wasteland, and is a dirty bomb, good reason to use nukemap
http://www.nuclearsecrecy.com/nukemap/
The best value for this is Air blast radius (20 psi). At this pressure, heavily built concrete buildings are severely damaged or demolished; fatalities approach 100%. So I think this is the best value
The area of Coney Island is 1.7896818 square kilometers (simplified to 1.79 square kilometers)
https://en.wikipedia.org/wiki/Coney_Island
To get 20 PSI air blast pressure, I get 41.56 kilotons of tnt which is 7-C