> For the complete documentation index, see [llms.txt](https://osl.mistium.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://osl.mistium.com/methods/numbers/.isprime.md).

# .isPrime()

## Description

isPrime returns a boolean indicating whether the input number is prime (a number greater than 1 that is only divisible by 1 and itself).

## Parameters

isPrime takes no parameters.

## Usage On Numbers

```javascript
// Basic usage
num = 17
log num.isPrime()
// true
// 17 is prime

num = 16
log num.isPrime()
// false
// 16 is not prime (divisible by 1, 2, 4, 8, 16)

// Works with larger numbers
log 997.isPrime()
// true
// 997 is prime

// Special cases
log 1.isPrime()
// false
// 1 is not considered prime by definition

log 2.isPrime()
// true
// 2 is the smallest and only even prime number

// Negative numbers and zero are not prime
log (-7).isPrime()
// false

log 0.isPrime()
// false
```


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