Have you heard? Numbers can have character traits! They can be temperamental or even suffer from personality disorders!
Some numbers are narcissistic! Some are honest or practical, and others are perpetually happy or sad.
You can use these slides to learn about these special integers and share them with students. Make your own copy HERE.
You might use these in several different ways:
- teach in succession as a mini-unit
- share over time- introducing one at a time
- save for a substitute or to use between units.
Here is a quick reference guide, with links to extra activities and resources.
QUICK REFERENCE GUIDE
| SPECIAL NUMBERS | RESOURCES |
HAPPY numbers are discovered by repeatedly finding the sum of the squares of the digits. If a number is “happy,” you will eventually get the number 1. If following these steps puts you in a loop, the number is SAD. | This is so fun! Sarah Carter of M+A+T+H = LOVE shares a wonderful lesson plan in this guest blog post. Students might also enjoy finding the happiest numbers (those reached in one to three steps) |
HONEST numbers are numbers that can be written in a word or words, using the same number of letters as the number itself. Example: 11 = two plus nine (11 letters) | All numbers greater than 13 are honest. If you get stuck trying to prove this, you’ll find some help HERE. |
NARCISSISTIC numbers are found by finding the sum of the digits raised to the power of the number of digits. If that sum is equal to the original number, it is narcissistic! | Example 153 has 3 digits so raise each digit to the power of 3 and find the sum) Add 13 + 53 + 33 = 1 + 125 + 27 = 153 There are only 89 in all. Use these questions to guide students into discovering the first few! |
| PRACTICAL numbers are determined when the factors of the number can be used or combined to get all the numbers preceding that number and the number itself. If your students have trouble with factorization, here is an easy method I used to teach my students! | Example 12 is a practical number – Its factors are 1, 2, 3, 4, 6, and 12. These factors can be used or combined to get all numbers, 1-12: 1 (1), 2 (2), 3 (3), 4 (4), 5 (1 + 4), 6 (6), 7 (3 + 4), 8 (2 + 6), 9 (3 + 6), 10 (4 + 6), 11 (1 + 4 + 6), 12 (12) Here’s a list of practical numbers to get you started! |
You may also like these activities:
Triple-A Analogies – includes a video tutorial
The Math Behind the Fun and Games ~ For Masterminds Who Love Wordle (video tutorials)
…many more found here!