1886 $2 Silver Certificate. Only Recently Noticed What Serial Number it is......

So I have this one bill that was handed down to me from my grandparents. It's in really nice shape but someone only recently pointed out what serial number it was.

In case anyone is wondering, it's not 21...its 2. I was just doing some research and found a 2006 auction during which they sold this exact same bill (same signatures and seal). They said it was the lowest known serial number (4), in uncirculated condition, for $28,000 plus. This one is definitely not uncirculated, but I don't think it's far off. It has a small fold in the middle and another light mark near his face. I'm interested to see what you guys think.

Here's mine (not great pictures): http://imgur.com/a/578LA

Here's the auction listing with price realized: http://images.goldbergauctions.com/php/lot_auc.php?site=1&sale=36&lot=4404