1432
There were no series of 1951 $100 bills ever printed.
1862
The first Federally-issued 100 bills were printed in 1862. Please check your bill again and post a new, separate question with more information that might help to ID it.
The U.S. never printed a $100 bill with that date. Please check again and post a new question.
Since the 1960s, the largest bill still in use is $100. Nothing larger has been printed since the 1940s.
Probably in 100 ac.
100 Thousand approx!
To clear things up, the bill wasn't printed in Philadelphia. That's the Federal Reserve District that distributed the bill, but it was printed in Washington. Please see the question "What is the value of a 1950 US 100 dollar bill?" for more information.
It means its a miss print.
As of 2014, there is not a 1 million dollar bill, although there are novelty ones printed. The highest bill of currency is 100 dollars.
Ulysses S. Grant is on the $50 dollar bill. This bill weighs about 1 gram, has an identifying watermark, and is printed on cotton and linen. It was first printed in 1861.
If you mean size, all notes printed before series 1928 were large sized. If you mean larger denomination, there were $500, 1000, 5000, 10,000, and 100,000 notes printed. Notes having a denomination of larger than $100 has not been printed since 1945.