The number 29 is written as XXIX in Roman numerals. The system of Roman numerals was developed centuries ago by the Romans and widely accepted. Later it was replaced by the decimal system of numbers.
The system of Roman numerals uses seven special symbols for writing various numbers. The system uses the symbols I, V, X, L, C, D and M. V stands for five, and X stands for ten. Larger numbers can be written by using the symbol L for 50, C for 100, D for 500 and M for a 1,0000. In the case of XXIX, the two X symbols equal 20, and the I before the X equals nine, totaling 29.