It is not possible to give a sensible answer to this question. The greatest common factor (GCF) refers to a factor that is COMMON to two or more numbers. You have only one term in the question!
The GCF is 6.
The GCF is 9.
The GCF is 4.
The GCF is 30.
50
The GCF is: 1
The GCF is 27.
The GCF is 1.
The GCF is 2.
The GCF is 3.
The GCF is 5.
The GCF of 125, 200 is 25.