Answer: 1
Definition: A factor is a divisor - a number that will evenly divide into another number. The greatest common factor of two or more numbers is the largest factor that the numbers have in common.
Method:
One way to determine the common factors and greatest common factor is to find all the factors of the numbers and compare them.
The factors of 13 are 1 and 13.
The factors of 81 are 1, 3, 9, 27, and 81.
The only common factor is 1. Therefore, the greatest common factor is 1, which means the numbers are relatively prime.
The greatest common factor of 16 72 and 81 is 1.
The Greatest Common Factor (GCF) is: 9
The greatest common factor is 9
The greatest common factor (GCF) of 36 81 and 144 is 9.
Short answer: There are none. There is neither a greatest common factor nor common factors of a single number, such as 81, because there cannot be any form of common factor without two or more numbers to compare. Common factors are factors that the numbers being compared have in common. The greatest common factor is the largest factor that all the numbers being compared have in common. Thus, since there are not two or more numbers to compare, there are neither common factors nor a greatest common factor. The factors of 81 are 1, 3, 9, 27, and 81. Examples: The common factors of 18 and 81 are 1, 3, and 9; the greatest common factor is 9. The common factors of 20 and 81 are only 1; the greatest common factor is 1. The common factors of 39 and 81 are 1 and 3; the greatest common factor is 3. The common factors of 81 and 243 are 1, 3, 9, 27, and 81; the greatest common factor is 81.
It is: 1
The greatest common factor of 52 and 81 is 1
The greatest common factor of 40 , 81 = 1
The greatest common factor of 81 and 189 is 27.
The greatest common factor of 56 and 81 is 1.
The Greatest Common Factor of 81, 108, 117: 9
The GCF of 53 and 81 is 1.
The greatest common factor of 16 72 and 81 is 1.
The greatest common factor of 58 and 81 is 1.
Greatest common factor of 81 and 123 is 3.
The Greatest Common Factor of 81, 21, and 14 is 1.
The greatest commmon factor of 81 and 67 is 1.