Composite Number Calculator

Input a number to check if it's a composite number, or define a range to generate all composite numbers within that range.

Composite Number Check or Generate

What Is a Composite Number?

A composite number is a natural number greater than 1 that has at least one factor other than 1 and itself. In simpler terms, a composite number can be evenly divided by numbers other than 1 and itself. Examples include 4, 6, 8, 9, and 10. Composite numbers stand in contrast to prime numbers, which only have two factors: 1 and themselves.

How to Determine If a Number Is a Composite Number

Follow these steps to check if a number is a composite:

  1. Eliminate Special Cases: Numbers less than 2 are neither prime nor composite.
  2. Test for Divisors: Divide the number by natural numbers starting from 2 up to the square root of the number.
  3. Evaluate the Result: If at least one divisor is found, the number is composite. If no divisor is found, the number is prime and not composite.

Examples

Example 1: Is 8 a Composite Number?

Solution:

Testing Divisors:

8 can be evenly divided by 2.

Result: 8 is a composite number.

Example 2: Is 87 a Composite Number?

Solution:

Testing Divisors:

87 can be evenly divided by 3.

Result: 87 is a composite number.

Example 3: Is 97 a Composite Number?

Solution:

Testing Divisors:

Check divisors from 2 to \( \sqrt{97} \approx 9.8 \): 2, 3, 4, 5, 6, 7, 8, 9, 10. None result in a whole number.

Result: 97 is a composite number; it is a prime number.

First 100 Composite Numbers

  • 4
  • 6
  • 8
  • 9
  • 10
  • 12
  • 14
  • 15
  • 16
  • 18
  • 20
  • 21
  • 22
  • 24
  • 25
  • 26
  • 27
  • 28
  • 30
  • 32
  • 33
  • 34
  • 35
  • 36
  • 38
  • 39
  • 40
  • 42
  • 44
  • 45
  • 46
  • 48
  • 49
  • 50
  • 51
  • 52
  • 54
  • 55
  • 56
  • 57
  • 58
  • 60
  • 62
  • 63
  • 64
  • 65
  • 66
  • 68
  • 69
  • 70
  • 72
  • 74
  • 75
  • 76
  • 77
  • 78
  • 80
  • 81
  • 82
  • 84
  • 85
  • 86
  • 87
  • 88
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 98
  • 99
  • 100
  • 102
  • 104
  • 105
  • 106
  • 108
  • 110
  • 111
  • 112
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 128
  • 129
  • 130
  • 132
  • 133