Number
79 in Roman numerals
79 is written LXXIX
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 LXXIX is built
Roman numerals are written one decimal place at a time, largest first.
- LXXtens · 7L (50) plus XX (20) makes 70.
- IXones · 9I before X means 10 − 1 = 9. This saves writing VIIII.
70 + 9 = 79
The pair IX 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 LXXVIIII (8 letters). That adds everything up without subtraction. The Romans sometimes wrote numbers this way, and clocks still show 4 as IIII, but today LXXIX (5 letters) is the standard.
About the number 79
- 79 is a prime number: only 1 and 79 divide it exactly.
- LXXIX has 5 letters. 604 of the numbers up to 1,000 have longer numerals.
Counting from 71 to 80
Every number from 71 to 80 starts LXX (70); only the ending changes.
| Number | Roman numeral |
|---|---|
| 71 | LXXI |
| 72 | LXXII |
| 73 | LXXIII |
| 74 | LXXIV |
| 75 | LXXV |
| 76 | LXXVI |
| 77 | LXXVII |
| 78 | LXXVIII |
| 79 | LXXIX |
| 80 | LXXX |