Question: Find the smallest positive integer whose cube ends in $7$.

Sat, 02 May 2026 23:11:24 +0000

**Why the Smallest Positive Integer Whose Cube Ends in 7 is More Than Just Math — It’s a Digital Curiosity Trend** Curiosity about numbers ending in specific digits isn’t new, but recent discussions around the smallest positive integer whose cube ends in 7 have gained surprising momentum online. This simple question taps into a growing interest in numeric patterns, cryptography basics, and digital puzzles that STEM enthusiasts and casual learners alike find engaging. What starts as a basic math curiosity reflects broader trends in mobile-first learning and algorithmic literacy — especially in the U.S., where users increasingly seek digestible, trustworthy explanations on niche topics. The cube of a positive integer n ends in 7 when n³ ≡ 7 (mod 10), meaning only one digit — 7 — satisfies this quadratic condition in base ten. By systematically testing small positive integers, the answer becomes clear: 3 is the smallest integer whose cube ends in 7, since 3³ = 27. This discovery invites deeper exploration of modular arithmetic, digit patterns, and how numbers behave under exponentiation — concepts foundational to computer science, coding, and digital trend analysis. **Why This Question Is Rising in Conversations Across the U.S.**