Skip to content / Đến nội dung
ThichHocToan.com

IMAS 2025-2026 Junior Division - First Round Question 18

IMAS · IMAS 2025-2026 Junior Division - First Round

Question 18

What is the sum of all positive integers $n\le200$ such that the sum of all distinct positive divisors of $n$ equals $2n-1$?
  1. $126$
  2. $127$
  3. $253$
  4. $254$
  5. $255$