A number with two prime factors that are not the same will have only four factors. It will have 1, itself, and those two prime factors as its factors.
Examples:
6 = 2 x 3. Its factors are 1, 2, 3, and 6.
15 = 3 x 5. Its factors are 1, 3, 5, and 15.
77 = 7 x 11. Its factors are 1, 7, 11, and 77.
Counter-examples:
4 = 2 x 2. Its factors are 1, 2, and 4.
12 = 2 x 2 x 3. Its factors are 1, 2, 3, 4, 6, and 12.
30 = 2 x 3 x 5. Its factors are 1, 2, 3, 5, 6, 10, 15, and 30.
45 = 3 x 3 x 5. Its factors are 1, 3, 5, 9, 15, and 45.
Prime numbers to the third power, like 8 and 27.
There are an infinite number of numbers with only four factors, started by 6, 8 and 10.
There are quite a few. 6 does. 8 does.
85 has four factors.
All composite numbers have more than 2 factors whereas prime numbers have only 2 factors
20 has six factors.
8 only has four factors.
Of the numbers from 1 to 30, only 30 has all three of those numbers as factors.
Because there are only four numbers that divide into those numbers evenly.
6, 8 and 10 are some numbers with four factors.
Because they have only two factors whereas composite numbers have more than two factors
18, 22, 26 and 30 have two of the same factors as 16.
Numbers having only 2 factors are prime numbers. Their only factors are 1 and themselves. Prime numbers. The only two factors should be 1 and itself.
Prime numbers only have one and itself as factors.
Numbers that have only 2 factors are prime numbers
Prime numbers have only two factors, 1 and themselves, so only prime numbers could have only two factors
53 is the only prime number out of the four numbers because it has only two factors.
No, only square numbers have an odd number of factors.
Four
Numbers whose factors only include one and themselves are called Prime numbers.