2, 4, 457, 914
No. Some proper factors are prime.
No, no prime number has proper factors.
One has no proper factors.
1 doesn't have proper factors.
Proper factors do not include one and the number itself.
Prime numbers don't have proper factors.
The proper factors of 35 are 5 and 7.
The proper factors of 26 are 2 and 13
Prime numbers don't have proper factors.
Prime numbers don't have proper factors.
Zero doesn't have any proper factors.
Prime numbers don't have proper factors.