ACM-ICPC online round participants can be found at https://docs.google.com/spreadsheets/d/e/2PACX-1vTUwGU2SM13hobkseuOIvIwYvPFJfXz0sBOYTwNbq6lG9tqHd1gigAPYwPhwIgt-ABGkhp4rl_r3yik/pubhtml
Now, I have downloaded the file and manipulated using pandas to find :
No. of Teams Registered = 1510
No. of Unique Colleges = 486
College With Maximum No. of Teams is International Institute of Information Technology - Hyderabad ( 58 teams)
Colleges arranged in descending No. of teams can be found Here :
Note : The data mentioned is NOT PERFECT as there are some misspell in college names.