18 in Roman Numerals
XVIII
18 in Roman numerals is XVIII, and is spelled eighteen.
How to write 18 in Roman numerals
To write 18 in Roman numerals, combine X (10) and VIII (8) to get XVIII.
The numeral XVIII is read from left to right, from the largest value to the smallest, adding each symbol as you go.
| Value | Roman |
|---|---|
| 10 | X |
| 8 | VIII |
| 18 | XVIII |
Facts about the number 18
- 18 is an even number.
- 18 is a composite number. Its prime factorization is 2 × 32.
- The digits of 18 add up to 9.
- 18 has 6 divisors.
18 in other number systems
| Decimal | 18 |
| Roman | XVIII |
| Binary | 10010 |
| Octal | 22 |
| Hexadecimal | 12 |
Frequently asked questions
How do you write 18 in Roman numerals?
18 is written as XVIII in Roman numerals.
What does the Roman numeral XVIII mean?
XVIII represents the number 18 (eighteen).
Is 18 a prime number?
No, 18 is a composite number.
What is 18 in binary and hexadecimal?
18 is 10010 in binary and 12 in hexadecimal.
Related numbers
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