Do you mean that thing at the 10 o'clock position? To me it looks like an evaporated drop of water. This should be easy to clean with a microfiber cloth and a drop of water.
If it isn't that, it could be on the inside of the lens, impossible to fix. Being so close to the edge, it probably would not affect your photos or footage, as you have said.
Remember that that glass is not actually the lens itself, but only the glass cover of it, which is why it may not affect the footage.