That would most likely be an 1847 Victoria gold Sovereign restrike.
A "restrike" is a coin struck at a later date using the original dies.
847 what?
The positive integer factors of 847 are: 1, 7, 11, 77, 121, 847
847+57=904
1247 - 847 = 400
850
5,082 = 847 X 6
847 121,7 11,11,7
847/1
847 is composite.
121
847 multiplied by 6 is 5,082.
84700