18.2) Ordinal Numbers

In the lessons Counting to 10 and Counting to 1000, you learned about Bulgarian cardinal numbers, used to denote a quantity. In this lesson, you will learn about ordinal numbers, used to denote a rank, or a position in a series (first, second, etc.).
Like adjectives, ordinal numbers have to agree in gender and in number with the noun they qualify. Here's the full inflection table for "първи", meaning "first":

This is a very regular inflection, and you can use the same forms for all ordinal numbers:

Examples
"Плащам наем на първия ден от всеки месец" - I pay rent on the first day of each month
"Борис е вторият ми син" - Boris is my second son
"Това е третият път, когато я виждам" - It is the third time I see her
Since the ordinal "ending" goes on the last number in a group, you can use those to create bigger ordinal numbers:

One exception though: the ordinal numerals for the hundreds, thousands, millions and billions are formed with the -ен ending (the е disappears in the feminine, neuter and plural forms):

• hundredth: стотен, стотна, стотно, стотни
• thousandth: хиляден, хилядна, хилядно, хилядни
• millionth: милионен, милионна, милионно, милионни
• billionth: милиарден, милиардна, милиардно, милиардни

Abbreviations

Ordinal numbers are abbreviated with the number followed by a dash and the last two letters: 1-ви, 2-ри, 3-ти…