# PHP Program to find Composite Number

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## What is Composite Number?

A positive integer that has at least one divisor other than 1 and itself.

Tips: It is recommended to use our online Composite Numbers calculator for better understanding.

## Examples

The following table provides few examples of composite numbers.

NumberDivisorResult
13 1, 13 Not a Composite Number
15 1, 3, 5, 15 Composite Number
47 1, 47 Not a Composite Number

## Using for loop

In the following example, we will check whether the number 12 is a Composite number or not using for loop.

### Example

PHP Compiler
<?php \$num = 12; \$count = 0; for(\$i=1; \$i<=\$num; \$i++) { if(\$num % \$i == 0) \$count++; } if(\$count > 2) printf("\$num is a composite number"); else printf("\$num is not a composite number"); ?>

## Using while loop

In the following example, we will check whether the number 12 is a Composite number or not using while loop.

### Example

PHP Compiler
<?php \$num = 12; \$count = 0; \$i = 1; while(\$num >= \$i) { if(\$num % \$i == 0) \$count++; \$i++; } if(\$count > 2) printf("\$num is a composite number"); else printf("\$num is not a composite number"); ?>

## Using do while loop

In the following example, we will check whether the number 12 is a Composite number or not using do while loop.

### Example

PHP Compiler
<?php \$num = 12; \$count = 0; \$i = 1; do{ if(\$num % \$i == 0) \$count++; \$i++; }while(\$i<= \$num); if(\$count > 2) printf("\$num is a composite number"); else printf("\$num is not a composite number"); ?>

## Composite Numbers between the Given Range

In the following example, we will find all the Composite numbers between 1 and 10.

### Example

PHP Compiler
<?php \$start = 1; \$end = 10; \$count = 0; \$i = 1; echo "Composite Numbers between \$start and \$end: <br>"; for(\$start=\$start; \$start<=\$end; \$start++) { for(\$i=1; \$i<=\$start; \$i++) { if(\$start % \$i == 0) \$count++; } if(\$count > 2) echo "\$start "; \$count = 0; } echo "<br>"; ?>

## Check Whether the Number is Prime or Composite

In the following example, we will check whether the number 12 is a Prime number or Composite number.

### Example

PHP Compiler
<?php \$num = 12; \$count = 0; for(\$i=1; \$i<=\$num; \$i++) { if(\$num % \$i == 0) \$count++; } if(\$count == 2) printf("\$num is a prime number"); else printf("\$num is a composite number"); ?>