Number Classification API

📌 Project Overview

The Number Classification API is a RESTful service that accepts a number and returns interesting mathematical properties about it, along with a fun fact from the Numbers API.

🚀 Features

• Check if a number is prime.
• Check if a number is perfect.
• Check if a number is an Armstrong number.
• Determine if a number is even or odd.
• Calculate the sum of its digits.
• Fetch a fun fact about the number.
• Returns structured JSON responses.
• Handles error validation and incorrect input.
• Fully deployed on Render.

🛠️ Tech Stack

• Node.js (Express.js)
• TypeScript
• Axios (for external API requests)
• Helmet & CORS (for security)
• Render (for deployment)

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📂 Folder Structure

number-classification-api/
│── src/
│   ├── constants/
│   │   ├── env.ts             # Environment variables
│   │   ├── routes.ts          # API route constants
│   ├── core/
│   │   ├── number/
│   │   │   ├── number.controller.ts   # Number classification logic
│   │   │   ├── number.routes.ts       # API routes
│   ├── utils/
│   │   ├── logger.utils.ts     # Logger utility
│── index.ts                    # Main Express server file
│── tsconfig.json                # TypeScript configuration
│── package.json                 # Project dependencies & scripts
│── .env                         # Environment variables

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🏃‍♂️ Getting Started

1️⃣ Clone the Repository

git clone https://github.com/ricky-ultimate/number-classification-api.git
cd number-classification-api

2️⃣ Install Dependencies

npm install

3️⃣ Set Up Environment Variables

Create a .env file and add:

PORT=5001

4️⃣ Start the Server (Development Mode)

npm run dev

5️⃣ Test the API Locally

Open your browser or use curl:

curl http://localhost:5001/api/classify-number?number=371

Expected Response:

{
  "number": 371,
  "is_prime": false,
  "is_perfect": false,
  "properties": ["armstrong", "odd"],
  "digit_sum": 11,
  "fun_fact": "371 is a narcissistic number."
}

---

🛠️ API Endpoints

GET /api/classify-number

Request:

GET /api/classify-number?number=28

Success Response (200 OK):

{
  "number": 28,
  "is_prime": false,
  "is_perfect": true,
  "properties": ["even"],
  "digit_sum": 10,
  "fun_fact": "28 is the 2^{nd} perfect number."
}

Error Response (400 Bad Request):

{
  "number": "abc",
  "error": true
}

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