What is the prefix of the word converged

The prefix is always at the beginning of the word. "pre-" meaning before. For converged, it would be the same thing as "converge". Unless it was the suffix, which would change between both words. For converged, get rid of the 'd' so that it can't try and confuse you. Now, you have the word "converge". The prefix would be "con-" which also means "with".