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한국어 → 🔁 Make a Palindrome

Make a number
that reads the same backward

Numbers such as 121 and 3773 that read the same forward and backward are called palindromes. Choose any number and repeatedly add it to its reversed form; most numbers become palindromes within just a few steps. Try it yourself.

Process: Choose a number and add its reversed value. If the result is not a palindrome, repeat the same process. (Example: 47 → 47+74=121, a palindrome! Success in just 1 step)
💡 Most numbers reach a palindrome quickly, but 196 is special. Even after billions of reverse-and-add operations, no one has confirmed that it becomes a palindrome. There is also no proof that it never will, making it an unsolved problem known as the "196 problem." For safety, this tool calculates up to 100 steps.