All United States currency is valid at face value. A bank would honor any of the notes I posted at face value, BUT you would be INSANE to do so, obvioulsy.

The only exception to that were the gold certificates that were illegal to own from 1933 to 1964 then they were valid again. (posted one couple of days ago).

#100 is the LARGEST denom. currently

The reason for the big notes in the 1930's was people were on a csah basis and there was little credit. Now (according to the BEP) the average large cash purchase is $42. Over that a credit card, debit card, or check is used, so the large notes were removed. (plus a few other reasons too)