2

The sum of all factors of 20 is 42. Its Prime Factors are 1, 2, 4, 5, 10, 20 and (1, 20), (2, 10) and (4, 5) are Pair Factors.

Its Prime Factors are 1, 5, 25, and (1, 25) and (5, 5) are Pair Factors.

• Factors of 25: 1, 5 and 25.
• Negative Factors of 25: -1, -5 and -25.
• Prime Factors of 25: 5.
• Prime Factorization of 25: 5 × 5 = 52
• Sum of Factors of 25: 31.

Factors of 20: 1, 2, 4, 5, 10 and 20. Prime Factorization of 20: 2 × 2 × 5 or 22 × 5.

Factors of 27

• Factors of 27: 1, 3, 9 and 27.
• Negative Factors of 27: -1, -3, -9 and -27.
• Prime Factors of 27: 3.
• Prime Factorization of 27: 3 × 3 × 3 = 33
• Sum of Factors of 27: 40.

The common factors for 27 are 3 and 9. Therefore the total number of factors that 27 has is 4 and they are 1, 3, 9, and 27.

The common factors of 18 and 27 are 1, 3 and 9. The greatest common factor of 18 and 27 is 9.

Answer: The smallest factor of 27 is 1.

So, the prime factorisation of 27 is 3 × 3 × 3 or 33, where 3 is a prime number.

27 (number)

No, 27 is not a prime number. The number 27 is divisible by 1, 3, 9, 27. For a number to be classified as a prime number, it should have exactly two factors. Since 27 has more than two factors, i.e. 1, 3, 9, 27, it is not a prime number.

As you can see when you list out the factors of each number, 6 is the greatest number that 12, 18, and 24 divides into.

The biggest common factor number is the GCF number. So the greatest common factor 18, 24, 30 is 6.

The gcf of 18 and 36 can be obtained like this: The factors of 18 are 18, 9, 6, 3, 2, 1. The factors of 36 are 36, 18, 12, 9, 6, 4, 3, 2, 1. The common factors of 18 and 36 are 18, 9, 6, 3, 2, 1, intersecting the two sets above.

6

4