2, 3, 6, 137, 274, and 411 are the proper factors of 822.
It is: 743 because it only has two factors
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.
Prime numbers don't have proper factors.
The proper factors of 22 are 2 and 11.
Prime numbers don't have proper factors.
Prime numbers don't have proper factors.
The proper factors of 26 are 2 and 13