There cannot be a greatest common factor of just one number. To be common there need to be at least two numbers. If you find all the factors of two or more numbers, and you find some factors are the same ("common"), then the largest of those common factors is the Greatest Common Factor.
The greatest common factor of 144 , 128 = 16
The Greatest Common Factor (GCF) of 64 and 128 is: 64
16 is the greatest common factor between 128 and 432.
The greatest common factor of 128 and 1000 is 8.
Greatest common factor of 128 and 75 is 1.
The greatest common factor (GCF) is 64.
The GCF of 128 and 512 is 128.
64
It is: 1
The GCF of 98 and 128 is 2.
The GCF of 128 and 168 is 8.
Since 8 is a factor of 128, it is automatically the GCF.