Swap numbered gems to line up four or more with a common prime factor. Divide their values, clear the gems that reach 1, and follow the falling pieces into new chains.
Runs in your browser — no download, no sign-up. About 40 MB to load the first time. Out now on Google Play and the App Store.
On a computer? Scan to get Factor Gems on your phone.
How it plays
Matching is about what numbers share. A 2, a 6, a 10 and a 14 can all belong to the same line: divide them by 2 and the first gem disappears while the others become 3, 5 and 7.
The board changes with every reduction, so each move invites you to look ahead and spot the next connection.
The Gem Workshop
From level 6, every cleared level pays out gems. In the Gem Workshop, merge two gems into their product (8 × 7 makes 56), split a gem back into its factors, or use a rare +1 or −1 gem to reach a prime. A short guided lesson shows the way.
256 gems, 256 stories
The Number Atlas holds every number from 2 to 257. Numbers you have seen show in grey; gems you have collected shine in full colour and open a real-world story on a sticky note.
Did you know? A piano has 88 keys. Every gem you collect unlocks a short, true story about its number, from history, science, geography and more.
In the free demo
- The whole first island, Sunny Summit: ten levels.
- The first five levels teach the game step by step.
- The Gem Workshop opens at level 6 with its own short lesson.
- All eleven languages and optional gem-layer rings that show each gem's factors.
- Share a card for every level you clear and every gem you collect.
In the full game
Fifty levels across five floating islands, with score stars, gem challenges and anchored gems to plan around. Earned +1, −1 and rainbow runes give you new ways to work the board, and the Gem Workshop turns your rewards into a collection of 256 gems and stories. Clear the adventure to unlock Endless Challenge: a run that starts with 20 moves and turns points into more chances to play. Prime levels after the first island have their own board shapes, and completing the Number Atlas earns a certificate and the Number Sage title.
Free to download. One purchase unlocks the full adventure for good — no ads, no subscription, no pay-to-win and no account. Out now on Google Play and the App Store.
For parents and teachers
Factor Gems is a playful number puzzle first. Its central move gives players repeated reasons to notice common factors and divisibility, without turning into a lesson. More for parents and teachers →
Your progress
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