# FACTOR BUSTER — Prime factorization showdown

> Prime factorization showdown (iPhone/iPad app by Shunsuke Kishino.)

- Source: https://appshunter.io/ios/app/factor-buster/id6824509964 (this page in markdown: same URL + `.md`)
- Developer: [Shunsuke Kishino](https://appshunter.io/developer/6784969791)
- Category: Games, Education, Casual, Puzzle
- Price: Free with in-app purchases
- Age rating: 9+
- Requires: iOS 17.0 · 172 MB
- Languages: American English, Japanese
- Released: 2026-10-20
- Data updated: 2026-10-26

## What is FACTOR BUSTER?

Break every number down into primes. Beat two bosses to clear — before time runs out.

FACTOR BUSTER is a prime factorization time attack.
A number appears in the middle of the screen. Tap the prime buttons below to divide it.
Each correct prime fires a beam; break the number down to 1 and it shatters in an explosion, and the next number flies in.

HOW TO PLAY
- Tap a prime that divides the current number
- A wrong prime costs 3 seconds
- The faster you solve, the more you score (bonus for no misses)
- The 5th number of each stage is a boss. Beat the stage 2 boss to clear

FIVE DIFFICULTIES
Easy, Normal, Hard, Extreme and God. Higher difficulties add bigger primes and take away 2, 3 and 5 — in God mode you fight with primes from 59 to 97 only.

TWO MODES
- Beginner: tap a dividing prime to attack at once
- Expert: tap primes to charge, then FIRE. The product stays hidden, so multiply in your head

FEATURES
- Random numbers every run, balanced by the number of primes and digits
- Music and backgrounds for each difficulty, ten bosses
- Touch controls that work with two thumbs
- Japanese and English
- No account. Just one short ad after every 5th game over (remove it with the one-time Remove Ads purchase)
- Records are stored only on your device

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Remove Ads | $2.99 | one-time |


## Is FACTOR BUSTER safe?

Not enough ratings yet to assess FACTOR BUSTER.

## Is FACTOR BUSTER legit?

FACTOR BUSTER appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for FACTOR BUSTER is 65 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 3 releases)

### 1.0.2 — 2026-10-25

Optimized for iPhone Duo. On the large inner screen and on iPad, the game now fills the whole screen with bigger prime buttons.

### 1.0.1 — 2026-10-23

Normal is now easier, with fewer prime buttons and smaller numbers. The old Normal challenge lives on in Hard.

### 1.0 — 2026-10-21

No release notes.

## More apps by Shunsuke Kishino

- [アゲログ](https://appshunter.io/ios/app/id6784969789)
- [nokori シンプルおこづかい管理](https://appshunter.io/ios/app/nokori/id6796372072)
- [Planet Dial](https://appshunter.io/ios/app/planet-dial/id6814144163)

All apps by Shunsuke Kishino: https://appshunter.io/developer/6784969791

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-26.*