Number
842 in Roman numerals
842 is written DCCCXLII
Type any other number or numeral below to convert it.
Above 3,999? Type the barred part in brackets, e.g. (IV)CC = 4,200.
How DCCCXLII is built
Roman numerals are written one decimal place at a time, largest first.
- DCCChundreds · 8D (500) plus CCC (300) makes 800.
- XLtens · 4X before L means 50 − 10 = 40. This saves writing XXXX.
- IIones · 2I written 2 times: 2 × 1 = 2.
800 + 40 + 2 = 842
The pair XL uses subtraction: a smaller letter before a larger one is taken away from it. Only six pairs work this way: IV, IX, XL, XC, CD and CM. More on subtraction
Mistakes to avoid
- Not DCCCXXXXII (10 letters). That adds everything up without subtraction. The Romans sometimes wrote numbers this way, and clocks still show 4 as IIII, but today DCCCXLII (8 letters) is the standard.
About the number 842
- 842 is even and can be split into prime factors: 2 × 421, or in Roman numerals II × CDXXI.
- DCCCXLII has 8 letters. 93 of the numbers up to 1,000 have longer numerals.
Counting from 841 to 850
Every number from 841 to 850 starts DCCC (800); only the ending changes.
| Number | Roman numeral |
|---|---|
| 841 | DCCCXLI |
| 842 | DCCCXLII |
| 843 | DCCCXLIII |
| 844 | DCCCXLIV |
| 845 | DCCCXLV |
| 846 | DCCCXLVI |
| 847 | DCCCXLVII |
| 848 | DCCCXLVIII |
| 849 | DCCCXLIX |
| 850 | DCCCL |