Grammar: Numbers and Quantity

Understanding Numbers

Russian numbers 1 through 4 have different forms depending on the gender of the noun they are modifying. For example, один (masculine), одна (feminine), одно (neuter) for “one”.
Numbers 5 to 20 are followed by nouns in the genitive plural in Russian. For example, пять книг (five books).
Numbers 21, 31, 41, etc., ending with ‘один’ behave like ‘one’ and will match the gender of the noun, whereas 22, 32, 42, etc., ending with ‘два’ follow the rules for ‘two’.

Numbers from 20 to 99 are written as a combination of a tens number and a unit number, like in English, but the tens number follows the unit. E.g., 35 - тридцать пять (literally, thirty five).
Hundreds are formed by attaching -сто to the end of the number. Example: двести - 200, триста - 300.
Russian thousands are expressed similarly to English, by adding a thousand to a smaller number, e.g., тысяча for one thousand, две тысячи for two thousands.

Use genitive case with numbers to express quantity. When a noun is associated with a number, it goes to the genitive case.
For numbers ending 2-4 (except for numbers ending 12-14), the genitive singular form of a noun is used. For numbers ending in 5-20, and for numbers ending in zero, the genitive plural form is used.

Words like “many” (много), “several” (несколько), and “few” (мало) also require the noun they modify to be in genitive case.
Remember that unlike English in Russian after numbers nouns can be in singular or plural form depending on context.

Ordinal numbers in Russian are similar to adjectives and conjugate according to gender, case and quantity.
They are used to talk about an order or arrangement of things. E.g., первый (first), второй (second), третий (third).