13 in Roman Numerals
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13 in Roman numerals is XIII. Split 13 by place value: 10 is X and 3 is III, and X + III joins into XIII. All its letters are added: 10 + 1 + 1 + 1 = 13. In lowercase it is xiii, and the number is thirteen.
How XIII is built
tens10 = 10 → X
10 is a single X.
ones3 = 3 × 1 → III
3 is three Is in a row: III.
What sets XIII apart
- Three Is: the limit
- XIII already has three Is in a row, the most the rules allow. That is why 14 is not XIIII but XIV.
- XII plus one I
- Coming from 12, XII, you only add another I.
- Longer than its neighbours
- XIII needs four letters, more than XII before it or XIV after it.
Where you see XIII
Sport
Super Bowl XIII was played on January 21, 1979, in Miami, where the Pittsburgh Steelers beat the Dallas Cowboys 35–31. Wikipedia The Games of the XIII Olympiad (1944) were cancelled because of the World War, but the Olympiad still kept its number. Wikipedia
Kings, queens and popes
Louis XIII was King of France from 1610 to 1643. Wikipedia
Films, games, books and software
Final Fantasy XIII was released in 2009. Wikipedia
Events and history
Julius Caesar crossed the Rubicon in 49 BC with Legio XIII Gemina. Wikipedia
Systems numbered with XIII
Factor XIII, the fibrin-stabilizing factor, was the last clotting factor to receive a Roman numeral, in 1963. Wikipedia
Numbers near 13
