A narcissistic number is a number that is the sum of its own digits each raised to the power of the number of digits. It is also known as a pluperfect digital invariant (PPDI), an Armstrong number (after Michael F. Armstrong) or a plus perfect number.
Narcissistic Numbers aren’t actually that confusing if you know how to do a couple things. Check out this math mini spark so that you can learn more about these peculiar numbers!
Spark your math thinking!
- Set up your math mini spark recording page: #32: Narcissistic Numbers
- Watch this video by Numberphile. Take notes on your recording page.
- Look at the list of Narcissistic Numbers on Wolfram Alpha. Record several of them.
- Pick a Narcissistic Number to “work out” on your recording sheet to prove it works. See example below.
5. Share your math mini spark recording page with your teacher/EY coordinator.