I dont think mathematicians care much about other mathematicians.

The physics department at my uni has a weekly colloquem that attracts physicists in all fields. (e.g. condensed matter, astro, hep-th, etc.)

There is a general chemistry colloquem too but it is in a tiny room and attracts small crowds.

There is nothing like that in the math department, really there are no topics that mathematicans are both working in and broadly interested in.