On Tuesday, the Obama administration acknowledged a cash payment of $1.7 billion made to Iran in January of this year, payment of a debt, the White House said, that was decades old.

The payment, according to The Associated Press, was made entirely in cash, using non-U.S. currency. The controversy over the payment has come as government officials admitted that the $1.7 billion installment came on the same day as four Americans being held in Iran were released – leaving critics to suggest the money was ransom.

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President Obama denied any connection to the release of hostages, saying the money was owed Iran from assets frozen in the 1970s.

How and why that much paper money was delivered on pallets to the country has baffled some. The administration says  it was done so because the U.S. government does not have a currency exchange system set up with Iran.

So what does it take to deliver $1 billion to a foreign country?

Obviously, it depends on the denomination of the bill.  The report says the money was paid in cash, using non-U.S. currency, but since our frame of reference is a dollar bill, let’s use those dimensions to take a look at just how much paper was delivered to Iran. (Note: The Euro, which was mentioned in the report as part of the currency delivered, is roughly the size of a U.S. dollar bill).

Here are some numbers, using a U.S. $100 bill (which has the same dimensions as a $1 bill) as a measure.

First, some base numbers: A packet of $100 bills (imagine a stack of bills wrapped by a paper ban) is less than 1/2" thick and contains $10,000. Each bill is 2.61 inches by 6.41 inches, making the area of a bill 16.7301 square inches.  A billion dollars in $100 bills would weigh 22,000 pounds, and be more than 1,100 cubic feet of paper.

Ok, now some comparisons.

  • A $10,000 stack of $100 bills can fit in your pocket.
  • If you have $100,000,000 (one hundred million), you will need a standard wood pallet.
  • When you hit $1 billion, you're talking real money – and area. You would need 10 crates of $100 bills to make up a billion dollars.  For the latest Iranian payment, nearly double that – 17 crates.
  • If stacked, the $1 billion in $100 bills would be 10,000 feet tall – imagine 10 Eiffel Towers stacked on top of each other.
  • It would take 16 weeks to count the $1 billion in $100 bills if you can count one bill per second.

What if you used $1 bills?

  • If you just stacked the $1 bills – one billion of them – they would go up 358,510 feet or 67.9 miles.
  • The area covered by 1 billion $1 bills would measure 4 square miles. This would cover an area equal to 2,555 acres. A football field is roughly one acre.
  • The length of 1 billion $1 bills laid end-to-end measures 96,900 miles. This would extend around the earth almost four times. So if we are talking about the January payment  to Iran, it would stretch around  the earth nearly eight times.
  • If you want to spend $1 billion, you'd better get busy. If you spend $1,000 an hour, it will take you 114 years to blow through the billion dollars.

Sources: Rutgers University; reference.com; The Associated Press