Cardinal numerals

Inflection

The cardinal numerals are mostly inflected regularly, like nouns. The exceptions are:

• yksi has the basic stem yhte ∼ yhde (e.g. essive yhtenä, genitive yhden), but the partitive is yhtä (consonant stem yh and suffix tä)
• kaksi is inflected like yksi, e.g. kahten : kahden : kahta
• kolme may or may not have boundary gemination, e.g. kolme kissaa may be pronounced as written or as kolmek kissaa; it is inflected as if it had no boundary gemination, with the e preserved as such, e.g. kolmen
• viisi has the basic stem viite ∼ viide (e.g. essive viitenä, genitive viiden), but the partitive is viittä (consonant stem viit and suffix tä); this is the same inflection as for e.g. the noun käsi (hand)
• kuusi is inflected like viisi
• seitsemän, kahdeksan, and yhdeksän are inflected as if the final n were missing, e.g. seitsemää : seitsemässä; in other words, their stem ends with a vowel, and the nominative has a special n ending, making the nominative and the genitive identical
• kymmenen is similar to seitsemän, e.g. the genitive is identical with the nominative and the inessive is kymmenessä; in addition, the partitive is kymmentä (consonant stem kymmen and suffix tä)
• tuhat has the inflection stem tuhante- ∼ tuhanne-, the partitive tuhatta, and the plural inflection stem tuhansi-; the form tuhannen, in addition to being the genitive, is sometimes used as the nominative, too.

Use of cardinal numerals

In Finnish, an expression consisting of a cardinal numeral and a noun has the noun in the partitive singular form, e.g. viisi taloa (five houses), when the expression as a whole is the basic form. When it is inflected, both words take the appropriate case form, in singular, e.g. viidessä talossa (in five houses). This is described in more detail in section Noun forms used with numerals.

When an expression containing a cardinal numeral is used as the subject of a clause, the predicate is in plural if the expression is definite, e.g. Nämä viisi maata tekivät… (These/The five countries made…). If it is indefinite, the predicate is in singular, e.g. Viisi maata teki… (Five countries made…). There is more information on this in section Singular and plural of verbs.

The nominative singular of a cardinal numeral also used when the numeral is part of a grammatical object. We say Yhtiö omistaa tämän talon (The company owns this house), where the object is in the genitive, but Yhtiö omistaa viisi taloa (The company owns five houses), where the object (viisi) is in the nominative. In negative statements, the partitive is used, according to the normal rules for the case of an object, e.g. Yhtiö ei omista viittä taloa.

The cardinal numerals are normally used in singular forms only. They appear in plural when the associated noun is one that is always used in the plural, such as housut (pants, trousers): kahdet housut (two pairs of pants), kaksien housujen (of two pairs of pants). See Plural of nouns. For such words, the numeral always congrues with the noun, even in the nominative. Even the word yksi is in plural in such a context: the Finnish name of the movie “Four Weddings and a Funeral” is Neljät häät ja yhdet hautajaiset.

Plural forms of numerals are also used in expressions like Otimme yhdet oluet (We took one beer [each]). In shortened forms such as Otetaan vielä yhdet (Let us take one more), the plural numeral (yhdet) is short for yhdet oluet or something similar.

The words for powers of ten, i.e. kymmenen (10), sata (100), tuhat (1,000), miljoona (1,000,000) etc. can be used like nouns in plural, e.g. sadat ihmiset näkivät sen (hundreds of people saw it), ostin kymmeniä omenia (I bought tens of apples). They can also be used in partitive singular with numeral-like attributes like monta (many), monta kymmentä omenaa (many tens of apples).