Writing out numbers on a check should be pretty straight forward.

Here's a list of the numbers you may need when filling out the cheque.

One = 1

Two = 2

Three = 3

Four = 4

Five = 5

Six = 6

Seven = 7

Eight = 8

Nine = 9

Ten = 10

Eleven = 11

Twelve = 12

Thirteen = 13

Fourteen = 14

Fifteen = 15

Sixteen = 16

Seventeen = 17

Eighteen = 18

Nineteen = 19

Twenty = 20

Twenty one = 21

You'll then need the major denominations:

Hundred = 100

Thousand = 1000

Million = 1000000

You may also need to learn the various denominations for the currency you are using (i.e. $ = dollars and ¢ = cents)

Here's a useful clip on how to write a cheque that you might want to watch too: