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 number in the question!
GCF of 140 and 25 is 5.
The GCF is 28.
The GCF is 35.
The GCF is 20.
The GCF is 2.
The GCF is 1.
The GCF is 20.
The GCF is 35.
The GCF is 20.
The GCF is 10.
The GCF is 4.
The GCF is 4.