Yes, eighty is a noun, it's a number, a thing. The word eighty is also used as an adjective. Example uses:
Noun: From the hundred we sent out, eighty responded.
Adjective: I've already read eighty pages of the assigned material.
Eighty six.
Eight thousand eighty.
Seven hundred and eighty five.
The word 85 is spelled as "eighty-five."
The correct spelling of the number is "one thousand, nine hundred and eighty six". The correct spelling of the year is "nineteen eighty six".
Countable
There is no contraction in the given sentence.The noun Davies should be possessive but it has no apostrophe to indicate possession.The correct possessive form for the singular noun Davies is:Davies' or Davies's (both are accepted as correct)Examples:Davies' life lasted eighty-two years from 1913 to 1995.Davies's life lasted eighty-two years from 1913 to 1995.
The ordinal number 80th is spelled eightieth.I swear this is the eightieth time I've had to help someone spell a word today.
Eighty dollars.
I spell it as eighty-one.
0.87 = eighty-seven hundredths 0.087 = eighty-seven thousandths 0.0087 = eighty-seven ten-thousandths 0.00087 = eighty-seven hundred-thousandths 0.000087 = eighty-seven millionths
Use a calculator, the answer is 560
Eighty-one quintillion.
75 is 54 percent of eighty!!!!!!!!!!!!!!
The number is eighty three (when used as an adjective, hyphenate as eighty-three).
Approximately 3.6% of the population in the United States are aged between eighty to eighty-nine years old.
eighty billion dollars eighty billion dollars eighty billion dollars