Format For Time In Seconds

I have a report that tells me how many items are completed every "x" seconds for a person. What I would like to do is when I enter that information into my spreadsheet is to have it calculate those seconds into minutes and seconds. (i.e. I will enter 105 (seconds) into a cell and I want it to display 1:45. Is there a formula or setting in the cell format that can do this? The problem I am going to have is that I will have to enter in each cell as seconds every time and then need it to convert to the minute and second format.