What does the 1600 furlongs represent?

And another angel came out from the altar, 

which had power over fire; 

and cried with a loud cry to him that had the sharp sickle, saying, 

Thrust in thy sharp sickle, and gather the clusters of the vine of the earth; 

for her grapes are fully ripe. 

And the angel thrust in his sickle into the earth, 

and gathered the vine of the earth, 

and cast it into the great winepress of the wrath of God. 

And the winepress was trodden without the city, and blood came out of the winepress, even unto the horse bridles, by the space of a thousand and six hundred furlongs.
Revelation 14:18-20

1600 is 4x4x100.

It represents completeness of the four corners of the earth.