Which city has the lowest number of patent applications?

What is the concept of "patent application"?

If you mean there are patent agencies, they don't exist in grades, and they may exist everywhere.

If it is a state organ, then only the local representative office of the Intellectual Property Office is responsible for the patent application, and it is not allocated according to the level. At present, Shenzhen is the lowest administrative level-not the provincial capital city.