That is the correct spelling of the number 57, but in US English, it is normally hyphenated fifty-seven as an adjective.
fifty-seven = 57.
Fifty-seven
seven thousand and fifty (:
Seven hundred fifty.
seven fifty-nine
The decimal number is "fifty and seven hundredths." In US currency, this would be "fifty dollars and seven cents."
three hundred fifty dollars and seventy cents or three hundred fifty point seven or three hundred fifty and seven tenths
750,000,000,000 is seven hundred and fifty billion.
one thousand seven hundred and fifty
Fifty-seven and three tenths.
fifty-seven and three tenths
one hundred and fifty-seven ( dollars, I presume )