OpenOlympiad
Concept 6 of 8Foundation
Video

Digit patterns & palindromes

A palindrome reads the same forwards and backwards: 121, 1331, 9009, RACECAR.

Digital root of a number = keep adding digits until you get a single digit.

Cool facts:

  • All multiples of 9 have digital root 9.
  • A 3-digit palindrome ABA is always divisible by... sometimes 11 (e.g., 121 = 11²).
Example
Digital root of 2,934: 2+9+3+4 = 18 → 1+8 = 9.
Is 1221 a palindrome? Yes (reverses to 1221).
💡 Tip:Use digital root as a quick check for divisibility by 3 and 9.
Prefer a video? Open YouTube search for “palindromic numbers digital root class 6

🎯 Try it!

5 questions to check what you just read.

0 / 5
  1. Q1.Which is a palindrome?
  2. Q2.Digit sum of 7,854:
  3. Q3.Digital root of 2,934:
  4. Q4.Which has digital root 9?
  5. Q5.3-digit palindrome between 200 and 300: