When you’re learning numbers and the alphabet, you may ask what number is spelled in alphabetical order in English? The answer is Forty, and it is the only number where its alphabets are in order.

Some people say “First” is also the number in which the letters are placed in alphabetical order. To be more precise, ‘Forty’ is the only cardinal number with its letters in alphabetical order. The word “first” also has its letters written in alphabetical order, but it is an ordinal number.

In this article, we’ll explain why Forty is the only number has its letters in alphabetical order when spelled out. Also, you’ll learn the math method of how Forty is calculated out. So you may calculate by yourself if you encounter such interesting number questions next time.

## Why The Number “Forty” is Spelled In Alphabetical Order

To identify whether a number is spelled in alphabetical sequence or not, you need to break down the letters and calculate each letter’s order.

So let’s break down Forty to five letters: F-O-R-T-Y, and count each position in the English alphabet. Then you’ll see as follows:

- F: the 6th letter
- O: the 15th letter
- R: the 18th letter
- T: the 20th letter
- Y: the 25th letter

These five letters are arranged from 6th, 15th, 18th, 20th, 25th in the alphabet, therefore, 40 is spelled in alphabetical order.

We can also analyze the ordinal number “First” in this way.

- F: the 6th letter
- I: the 9th letter
- R: the 18th letter
- S: the 19th letter
- T: the 20th letter

And you’ll see it is also arranged in alphabetical order.

## How to Figure Out Forty is the Only Number

You may ask how can you make sure Forty is the only number spelled in alphabetical order? Here are the calculation processes:

In order to figure out which number is arranged in alphabetical order, you don’t need to spell out every number from 1 to 1,000 or more. All you have to do is to check 1-19, 20, 30, 40, 50, 60, 70, 80, 90, 100, 1,000, million, billion, and trillion.

For example, the word “one” is composed of the letters “o,” “n,” and “e,” but they are not in alphabetical order. Likewise, the words two to nineteen, twenty, thirty, fifty, sixty, seventy, eighty, ninety, hundred, thousand, million, billion and trillion are all not spelled in alphabetical order.

## Final Thought

Figuring out that forty is the only number spelled in alphabetical order can be both a fun and educational exercise.

It’s fascinating to discover more about numbers and letters, as well as other interesting facts. For example, you may find “One” is the only number with its letters in reverse alphabetical order in your next exploration.