I've found a four-digit number ABCD
such that ABCD=(A+B+C+D)3
What is it ?
Is it unique?
(In reply to Paper & Pencil solution (spoiler)
by Steve Herman)
You rate me 3, and I rate you 6!
However, 512 is not a 4-digits number - no need to post disclaimers!
Both 17,18 as answers were known to me, however I've considered disclosing the "neighboring" feature as counterproductive...