Interesting Facts about Roman Numerals

Roman Numerals, as the name suggests, are the numbers written in the way ancient Romans used to write. These numerals are denoted by the symbols, alphabets, and follow specific rules and principles in the course of the formation. The alphabets are I, V, X, L, C, D, and M, these stands for 1, 5, 10, 50, 100, 500, and 1,000 respectively in the Hindu-Arabic numeral system.

Roman Numbers are made exclusive since their birth as they have a rich historical significance, and a lot of exciting things go by if we get involved in these symbols. Be it addition, subtraction, it is done in a unique way to form these symbols. Let’s delve a bit deeper and find more about it.

Some Interesting Facts about Roman Numerals

  • Preliminary pages are traditionally numbered in lower-case Roman numerals (i, ii, iii, iv, v, etc.). This helps to prevent renumbering the remaining book when front-matter content is changed, or additions are made at the last minute.
  • These are used to show the month in dates. Roman numerals are also used as a short method of writing ordinals in Poland.
  • Since this number system was developed for knowing the price of goods, and to carry on trade activities, there is no 0 in Roman numerals.
  • In the Baltics and Russia, the days of the week are often written as Roman numbers, for, eg. “I” stands for Monday.
  • Monarchs, Popes, Patriarchs, or other leading figures, are sometimes counted with Roman numbers, e.g., Queen Elizabeth II, Pope John Paul II, Pope Benedict XVI, Patriarch Alexius II. This is done because the same name is used for a lineage.
  • In Clocks with roman numerals, number 4 is denoted by IIII instead of the correct symbol IV to maintain symmetry.

Addition and subtraction in roman numerals in itself is an interesting task, let’s see some with examples.

While Adding,

The following number denoted by an alphabet is always added to the preceding one, and addition can be done thrice. For, eg.

VI (5 + 1) = 6

LXX (50 + 10 + 10) = 70

MCC (1000 + 100 + 100) = 1200

While Subtracting,

Subtraction in roman numerals follows a lot of rules such as:

  • Only subtract powers of 10 (I, X, or C, but not V or L). For, eg.
  • For 95, we don’t write VC (100 – 5) instead it is written as XCV (XC + V or 90 + 5)

  • Only subtract one number from another, for, eg.
  • For 13, don't write IIXV (15 – 1 - 1), write XIII (X + I + I + I or 10 + 3)

  • A number cannot be subtracted from another that is more than ten times higher (that is, you can subtract one from 10 [IX] but not one from 20—there is no such number as IXX.)
  • For 99, we do not write IC (C – I or 100 - 1). It is written as XCIX (XC + IX or 90 + 9).


The thing about roman numerals is there are certain alphabets or symbols we can constitute thousands of numbers just by rearrangement of these alphabets. Therefore, everything about roman numerals is exciting and deserves to be known.