509 in words

509 is written "five hundred nine". British English inserts "and" before the final part, giving "five hundred and nine"; American English leaves it out.

Where each word comes from

The same number, other ways

In words (US)

Five hundred nine

In words (UK)

Five hundred and nine

Ordinal

509th — five hundred ninth

Roman numeral

DIX

Digits

509

Writing it on a cheque

On a cheque the amount line reads "Five hundred and nine and 00/100" — or "Five hundred and nine only" in Indian and much of Commonwealth practice. The fraction or the word "only" exists to stop anyone appending digits after what you wrote. Draw a line through any space left over for the same reason.