With a date of 1792 it's NOT a Mint Issue coin. The first silver dollars were struck in 1794 and did not have Washington on them. Take it to a coin dealer to find out what it is and if it's worth anything.
The U.S. did not start making half dollars until 1794. You may have a privately-manufactured piece, a fantasy coin, or a counterfeit. Please post a new question with a more complete description of the coin to help ID it.