There are none.
Zero doesn't have any proper factors.
Zero. 5 is a prime so its only factors are 1 and 5. It, therefore, has no proper factors.
Every number is a factor of 0. However, 0 has no proper factors since no two numbers that are non-zero can multiply to give 0.
Zero is not a factor of 4. Zero is only a factor of zero! The factors of 4 are 1, 4, 2 The factors of zero are zero and any other number. Therefore the common factors are 1,2 and 4
No. Some proper factors are prime.
Yes.
No, no prime number has proper factors.
1 doesn't have proper factors.
One has no proper factors.
Proper factors do not include one and the number itself.
All numbers have common factors greater than zero.
The proper factors of 26 are 2 and 13