How to write 2021 in Roman numerals
Roman numerals are built place by place, from the largest value to the smallest. For 2021 the places are 2000 (thousands), 20 (tens), 1 (ones).
- Write 2000 as
MM. - Write 20 as
XX. - Write 1 as
I.
Joined together, MM + XX + I gives MMXXI.
2021 digit by digit
| Place | Value | Numeral | Rule used |
|---|---|---|---|
| thousands | 2000 | MM | the symbol repeated twice |
| tens | 20 | XX | the symbol repeated twice |
| ones | 1 | I | one symbol |
Check MMXXI by reading it back
Reading MMXXI from left to right and adding the pieces: MM = 2000, XX = 20, I = 1. Together that is 2000 + 20 + 1 = 2021, so MMXXI and 2021 match.
Mistakes to avoid with MMXXI
- Never repeat a symbol more than three times in a row. When a fourth would be needed, the subtractive form takes over.
- Only I, X and C may be placed before a larger symbol to subtract, so MMXXI never contains forms such as VX or LC.
- Read MMXXI as one number, not letter by letter: add the values left to right, except where a smaller symbol sits before a larger one.
Facts about the number 2021
- 2021 is an odd number and composite, with prime factors 43 x 47.
- In binary 2021 is
11111100101and in hexadecimal it is7E5. - Written out, 2021 is "two thousand twenty-one".
- The digits of 2021 add up to 5.
- As a year, 2021 was a common year with 365 days and belongs to the 21st century.
Where you will see 2021 in Roman numerals
Copyright lines for media released in 2021 show MMXXI in the closing credits. Production companies use Roman numerals for the year to maintain the standard legal formatting expected across the film and television industries worldwide.
Numbers near 2021
FAQ
What is 2021 in Roman numerals?
2021 is written MMXXI in Roman numerals. It is built from MM (2000), XX (20), I (1).
How do you write 2021 in lowercase Roman numerals?
Lowercase Roman numerals use the same rules, so 2021 is mmxxi. Lowercase is common for page numbers in a book's preface and for outline levels.
How do I convert any number to Roman numerals?
Split the number into thousands, hundreds, tens and ones, write each part with the symbols I, V, X, L, C, D and M, then join them from largest to smallest. Or paste it into the Roman numeral converter, which also converts back.
More roman numerals
- 2020 (MMXX): previous page
- 2022 (MMXXII): next page
- Roman numerals chart: the full list