Numbers

Numbers have a feminine and a masculine form. With a noun, use the form that matches the noun's gender. From 3 to 10 the masculine forms are the ones ending in -a, the opposite of what you might expect.

Zero is אֶפֶס efes. When there is no noun, as in counting aloud, phone numbers and telling the time, use the feminine forms.

With a noun

One comes after the noun, like an adjective. Two becomes שְׁנֵי shnei (m.) or שְׁתֵּי shtei (f.) before a noun. From three on, the number comes before the noun.

• סֵפֶר אֶחָד
  sefer ekhad
  one book
• שְׁנֵי סְפָרִים
  shnei sfarim
  two books
• שָׁלוֹשׁ מְכוֹנִיּוֹת
  shalosh mekhoniyot
  three cars
• יֵשׁ לִי שְׁנֵי אַחִים וְאָחוֹת אַחַת.
  yesh li shnei akhim ve'akhot akhat
  I have two brothers and one sister.
• הוּא בֶּן חָמֵשׁ.
  hu ben khamesh
  He's five years old.
• הַשָּׁעָה שֶׁבַע.
  hasha'a sheva
  It's seven o'clock.

11 and up

11 to 19 are a unit plus עֶשְׂרֵה esre (f.) or עָשָׂר asar (m.). In the feminine some units shorten, as in 13 below, 17 שְׁבַע עֶשְׂרֵה shva esre and 19 תְּשַׁע עֶשְׂרֵה tsha esre.

The tens are the same for both genders. Units follow with ו: עֶשְׂרִים וְאַחַת esrim ve'akhat 21, שְׁלוֹשִׁים וְחָמֵשׁ shloshim vekhamesh 35.

200 is מָאתַיִם matayim and 2,000 is אַלְפַּיִם alpayim, both dual forms.

First, second, third

Ordinals act as adjectives: רִאשׁוֹן rishon first, שֵׁנִי sheni second, שְׁלִישִׁי shlishi third. The days of the week are numbered from Sunday: יוֹם רִאשׁוֹן yom rishon "Sunday", יוֹם שֵׁנִי yom sheni "Monday". More in Dates and time.