Don't bother with the =A1, just highlight the column with the text, and drag the fill cursor all the way to the right till you hit column SF (that's the 500th column). It'll take a few seconds holding it there while it scrolls, but it also copies the formatting.
ETA: Even better solution. Type SF1 into the Name Box (that's the thing to the left of the formula bar, which will navigate you to cell SF1. Type 1, or anything else into that cell. Click CTRL+HOME and select the data you want to copy. With the source data selected, hit CTRL+SHIFT+(right arrow). Then hit CTRL+R.