If the numbers from One to One Thousand are written as words, there is no one number that has more letters than all the others - which is a shame, but there we are!
However, there are some numbers that are all equally the longest, in terms of number of letters.
What is the number of letters in these longest numbers?
How many are there of that length?
And what are they?
Taking the numbers from One to Nine, three of them have five letters - Three, Seven and Eight.
Taking the numbers Twenty, Thirty etc., Seventy has the most letters with seven.
Putting numbers together in the form <number> Hundred and Seventy <number>, where the <number> can be Three, Seven or Eight we get
Three Hundred and Seventy Three
Three Hundred and Seventy Seven
Three Hundred and Seventy Eight
Seven Hundred and Seventy Three
Seven Hundred and Seventy Seven
Seven Hundred and Seventy Eight
Eight Hundred and Seventy Three
Eight Hundred and Seventy Seven
Eight Hundred and Seventy Eight
So there are nine numbers with 27 letters.