There is not a $1,000,000 or even a $500 bill. There used to be $500 and $1,000 bills, but not anymore.
The first $1 U.S. bill was printed in 1862 and was referred to as legal tender. George Washington was first put on the $1 bill in 1869 to honor him as the first president.
The $2 bill has not been discontinued and is still in circulation, although it is rarely used.
Gas prices are different due to laws that require specific formulations that artificially limit supply in some areas. Also, gas prices are sometimes higher due to taxes.
Making money is actually a much more complicated process than you might think. There are incredible processes involved in order to protect the currency from counterfeiters or people committing fraud. U.S. paper money is made at the Bureau of Engraving and Printing. Currently, our paper money is made up of 25% linen and 75% cotton. Red and blue fibers of various lengths are distributed evenly throughout the paper in order to protect from fakes. There are five steps that how money is made, first going through a siderographer, who duplicates an engraving over and over multiple times through a process called Intaglio printing. Intaglio printing is a high-speed rotary press which produces over 8,000 sheets of money per hour. The second step is plate making, which the die is put under pressure, heated, and an impression of it is cast into plastic. The next step is the printing step, which goes to the Intaglio high-speed printers. Examining is the fourth step, which is where a specially authorized person examines the money for defects. If it is accepted, it is sent to the next step of overprinting. Overprinting is where a letterpress is used to print the Federal Reserve District seal and its serial number in green ink on the bill. The units of money are then banded together and packaged into bricks, containing 4,000 notes.
As you can see, this a very time-consuming process. You can read more about the production of money here: http://www.moneymuseum.com/standard_english/raeume/geld_machen/werkstatt/papiergeld/papierdruck/papierdruck_unten.html
Money Smart Kid