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 , 133 = 1
The greatest common factor of 12 and 385 is 1.
The Greatest Common Factor (GCF) is: 1
Greatest common factor of 12 51 and 92 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 3, 5, and 12 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.