Can numbers be called palindromes?

Numbers which read the same backwards and forwards (e.g. 717), are they still called palindromes, or is there another word for numbers like that?

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SW-User Best Comment

They are called palindromes, yes, or "palindromic numbers".

If you take a number that's not a palindrome and reverse its digits and add the two together, you will eventually get a palindrome, though it may take a few steps:

41 + 14 = 55 (one step)
57 + 75 = 132 + 231 = 363 (two steps)

Don't try this with the number 196, though. It's been done with over a billion steps and they still haven't found a palindrome.

NankerPhelge · 61-69, M

@SW-User It's weird, but my example number 717 (which I chose because I saw a car with 717 on the number plate near my house today) only divides by 3 and the non-palindromic number 239. It has no other factors. Why do you think that is?

How did you know about 196? Have you tried it yourself? Lol :)

SW-User

@NankerPhelge Dunno. But at least you can tell it divides by three because its digits add up to 15, which is a multiple of 3. Palindromic numbers can be prime (like 151, 313) or they can even be square numbers (like 121, 484).

I only know about 196 because I remember being told about it in elementary school. They're called "Lychrel numbers": https://en.wikipedia.org/wiki/Lychrel_number

NankerPhelge · 61-69, M

@SW-User I've never heard of Lychrel numbers before. That's a new one on me. I remember learning that 14 times 14 was 196.

SW-User

@NankerPhelge Yep. And 13 times 13 is 169. (and 31 times 31 is 961). I love noticing all these patterns. They call it "recreational mathematics". :)

NankerPhelge · 61-69, M

@SW-User I call 169, 196 and 961 anagrams. Lol :)