690 in Roman numerals

690 in Roman numerals is DCXC.

Pick any whole number from 1 to 3,999.

690 = \text{DCXC}

How to work it out

1
Take the biggest Roman value that fits, write its letter, subtract it, and repeat.
2
Here: 500 (D) + 100 (C) + 90 (XC) = 690.
3
Joined together: DCXC. (Four of the same letter in a row is never used: 4 is IV, 9 is IX, 40 is XL, 90 is XC, 400 is CD, 900 is CM.)

What is 690 in Roman numerals?

DCXC.

How do you read DCXC?

DCXC = 500 + 100 + 90 = 690.