18 in Roman Numerals
18
XVIII
eighteen
How XVIII is formed
| Place | Value | Symbols |
|---|---|---|
| Tens | 10 | X |
| Units | 8 | VIII |
| Total | 18 | XVIII |
XVIII is written one place at a time, from the largest to the smallest: X (10) + VIII (8) = 18.
Common mistakes
Wrong: XIIX
Why isn't 18 written as XIIX?
Only one smaller symbol can stand before a larger one, so IIX doesn't work. 8 is VIII (5 + 3), so 18 is XVIII.
Where you'll see XVIII
Super Bowl XVIII was played on January 22, 1984 at Tampa Stadium in Tampa: the Los Angeles Raiders beat the Washington Redskins 38–9.
The Games of the XVIII Olympiad were held in Tokyo in 1964.
The XVIII Olympic Winter Games were held in Nagano in 1998.
Using XVIII
For an 18th birthday card, cake topper or tattoo, the number is written XVIII: an X followed by VIII. Design it for a tattoo or a print
As the day of a date, 18 is XVIII: December 18 is XII.XVIII written month.day, or XVIII.XII written day.month. Convert a full date
Numbers near 18
Properties of 18
- Prime factors
- 2 × 3²
- Divisors
- 1, 2, 3, 6, 9, 18
- Even or odd
- Even
- Prime number
- No
- Letters in XVIII
- 5
With 5 letters, XVIII is longer than the Roman numeral of any smaller number.
18,000 in Roman numerals
With a bar over it (vinculum), X̅V̅I̅I̅I̅ means 18 × 1,000 = 18,000. How Roman numerals work