In Spanish, the written numbers are the same. (8 is still 8.) But as for spelling than, Spanish has Spanish words for one, two, nineteen, etc.

Below, the numbers from zero to thirty one are listed. Try to memorise them, like everything else in this book. (Remember, Quizlet rocks!)

(0) zero
cero

(1) one
uno

(2) two
dos

(3) three
tres

(4) four
cuatro

(5) five
cinco

(6) six
seis

(7) seven
siete

(8) eight
ocho

(9) nine
nueve

(10) ten
diez

(11) eleven
once

(12) twelve
doce

(13) thirteen
trece

(14) fourteen
catorce

(15) fifteen
quince

(16) sixteen
dieciséis

(17) seventeen
diecisiete

(18) eighteen
dieciocho

(19) nineteen
diecinueve

(20) twenty
veinte

(21) twenty one
veintiuno

(22) twenty two
veintidós

(23) twenty three
veintitrés

(24) twenty four
veinticuatro

(25) twenty five
veinticinco

(26) twenty six
veintiséis

(27) twenty seven
veintisiete

(28) twenty eight
veintiocho

(29) twenty nine
veintinueve

(30) thirty
trienta

(31) thirty one
trienta y uno

In Spanish, the numbers from zero to fifteen have their own unique names. The numbers from sixteen to nineteen have names that are really two numbers that are linked by "i". (Example- dieciocho.)

The numbers twenty-one to twenty-nine have names that consist of the names of two smaller numbers and also are joined into one word by the letter "i". (Example- veintitrés.)

Starting with thirty-one, numbers are written as separate words with a "y" between them, meaning 'and'. (Example- trienta y uno.) (Thirty-one)

In addition to counting and giving numbers, these numbers can be used to tell how many things there are;
-dos clases
-catorce libros
-viente estudiantes

Also, the number "uno" (including veintiuno, treinta y uno, etc.) becomes "una" before feminine nouns. (Example- "Tengo un hermano y una hermana."

Asking for Phone Numbers:
What's your phone number? = ¿Cuál es tu teléfono?
(Response-) It's one-two-three-four-five-six-seven. = Es uno-dos-tres-cuatro-cinco-seis-siete.
~~~~~~~~~~~~~~~~~~~~~~~~~
What's Rosita's telephone number? = ¿Cuál es el teléfono de Rosita?
(Response-) It's seven-six-five-four-three-two-one. = Es siete-seis-cinco-cuatro-tres-dos-uno.

*y means 'and'

The word twenty looks weird now... xD