# Calculator # vs Prime Factorization

Calculator # and Prime Factorization both sit at 4.6 stars, but that hides the real split: 100% of Prime Factorization's written reviews are positive against 60% of Calculator #'s. Prime Factorization also leads on in-app purchases (none vs 6) and ads (none vs shown). Calculator #'s advantage is ratings volume (36K vs 5). On price, rating, update cadence and device support there is nothing between them.

Both are free to download. Calculator # sells 6 in-app purchases, starting at $1.49 per month. Prime Factorization asks for nothing beyond the download.

Calculator # holds the better App Store score, 4.6 against 4.4. That said, the two scores are not equally well evidenced: Calculator # has 36K ratings behind it against 5, so its average is the more settled of the two. Written reviews complicate that: 60% of Calculator #'s written reviews are positive against 100% of Prime Factorization's, so the app with the better star average is not the one people write more warmly about.

Calculator # ships an update every 2 months, Prime Factorization every 3 months. The most recent releases landed on October 31, 2026 and October 15, 2026 respectively.

## The numbers

| Metric | Calculator # | Prime Factorization |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (36K ratings)](https://appshunter.io/ios/app/calculator/id458535080/reviews)** | [4.4 (5 ratings)](https://appshunter.io/ios/app/prime-factorization/id528980227/reviews) |
| Number of ratings | **36K** | 5 |
| Positive reviews | 59.5% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 2 months** | Every 3 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 57 MB | 2 MB |
| Requires iOS | 12.1 | **8.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Incpt.Mobis](https://appshunter.io/developer/445261166) | [Sohei Mori](https://appshunter.io/developer/528980270) |

## What reviewers say

### Calculator #

[App page](https://appshunter.io/ios/app/calculator/id458535080)

This multi-function calculator offers basic to advanced scientific and algebraic computations. It includes features like handwriting recognition, equation solvers, and 2D graphing, making it suitable for students and professionals. In-app purchases unlock advanced capabilities.

**Highlights:** Math Photos Solver, Handwriting Recognition, AI Math Problem Solver, Mathematical Display, Equation Solvers, 2D Graphing, Algebraic Functions

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PRO Upgrade 1 Month | $1.49 | per month |
| PRO Upgrade 3 Months | $2.99 | per 3 months |
| PRO + Recognition 1 Month | $4.99 | per month |
| PRO + Recognition 3 Months | $11.99 | per 3 months |
| 250 AI Recognition & Queries | $0.99 | one-time |
| 600 AI Recognition & Queries | $1.99 | one-time |

**What reviewers like**

- 👍 Easy to use
- 🚀 Powerful functionality
- 💡 Helpful for math classes
- ⭐ Great for students
- 👌 Works like a real calculator

**What reviewers complain about**

- 🔍 Confusing interface after update
- 📢 Too many intrusive ads
- 💰 Paywall for advanced features
- 🐛 Incorrect calculations
- 🔇 Loud audio ads

**Reported bugs**

- Crashes when trying to use certain functions
- Handwriting recognition not working reliably
- Inability to input negative numbers

**Requested features**

- Add option to turn off animation
- Improve ad placement to avoid obstructing usage
- Provide more transparency on paid features


### Prime Factorization

[App page](https://appshunter.io/ios/app/prime-factorization/id528980227)

This utility app breaks down integers into their prime factors. It also calculates the number and sum of divisors, lists all divisors, and identifies specific number types like prime, perfect, abundant, or deficient.

**Highlights:** Prime factorization of integers, Calculate number of divisors, Sum of divisors calculation, List all divisors, Identify prime numbers, Identify perfect, abundant, deficient numbers

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Calculator # free?

Calculator # is free to download, with in-app purchases available.

### Is Prime Factorization free?

Prime Factorization is free to download, with no in-app purchases.

### Which has better reviews, Calculator # or Prime Factorization?

Calculator # is rated higher. Calculator # averages 4.6 out of 5 from 36K ratings, while Prime Factorization averages 4.4 from 5 ratings.

### Do Calculator # or Prime Factorization have ads?

Calculator # shows ads; Prime Factorization does not.

### Which is updated more often, Calculator # or Prime Factorization?

Calculator # ships an update every 2 months, and Prime Factorization every 3 months. Most recently, Calculator # was updated on October 31, 2026 and Prime Factorization on October 15, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*