There's a lot of them.
6, 12, 18 and others
There is no Greatest Common Factor (GCF) for a single number. The Greatest Common Factor (GCF) is the largest factor common to two or more given numbers.
The greatest common factor of 42 and 12 is 6.
The greatest common factor of 42 and 66 is 6.6
The Greatest Common Factor (GCF) is: 6The greatest common factor of 42 and 102 is 6.
The Greatest Common Factor of 24 and 42 is 6.
The greatest common factor of 16 and 42 is 2.
The greatest common factor of 42 and 196 is 14.
The greatest common factor of 13 and 42 is 1.
The greatest common factor of 12 , 42 = 6
The greatest common factor (GCF) refers to a factor that is COMMON to two or more numbers. You have only one number in the question! The greatest factor of any number is itself.
There is neither a greatest common factor nor common factors of a single number, such as 42, because there cannot be any form of common factor without two or more numbers to compare. Common factors are factors that the numbers being compared have in common. The greatest common factor is the largest factor that all the numbers being compared have in common. Thus, since there are not two or more numbers to compare, there are neither common factors nor a greatest common factor. The factors of 42 are 1, 2, 3, 6, 7, 14, 21, and 42. Examples: The common factors of 25 and 42 are only 1; the greatest common factor is 1. The common factors of 36 and 42 are 1, 2, 3, and 6; the greatest common factor is 6. The common factors of 42 and 49 are 1 and 7; the greatest common factor is 7. The common factors of 42 and 60 are 1, 2, 3, and 6; the greatest common factor is 6. The common factors of 42 and 70 are 1, 2, 7, and 14; the greatest common factor is 14.
Since 3 is a factor of 42, it is automatically the GCF.