It can be and it is.
The Greatest Common Factor (GCF) of 1 and 12 is 1
The greatest common factor of 91 , 12 = 1
The Greatest Common Factor of 3, 8, 12: 1
The greatest common factor of 12 and 385 is 1.
The greatest common factor of 12 , 133 = 1
The Greatest Common Factor (GCF) is: 1
Greatest common factor of 12 51 and 92 is 1.
The greatest common factor of 3, 5, and 12 is 1.
The Greatest Common Factor of 12, 44, 15: 1
The Greatest Common Factor of 23, 12, 8 is 1.
The greatest common factor of the numbers 12 and 25 is one.
The GCF of 13 and 24 is 1.The GCF is 1.