Is there a formula to calculate min distance between a power cable and an RF cable to minimize interference?

 

There probably is, but youll never gather the required data to make it work. But power cables and RF cables work at extremely different frequencies, so interference between them is not a problem.
Problems arise when the high frequency signal is in the 10s to 100s of kHz. That can affect other equipment .
Best practice is to keep cables as far apart as possible; dont run them in parallel; rey crossing cables at right angles; dont put power cables andlow level signal cables in the same conduit.

 

The required distance will also depend on the effectiveness of any shielding that the cables may have. It also depends very much on the power levels in the cables and the sensitivity to interference of the receiving ends devices. There are many "design rules" that offer general advice, but not much in the line of formulas.