There are 32 factors. These are 2n and 131071*2n for n = 0 to 15, and
It is the sum of all its factors (other than itself).
Yes, as has been known since 1588 For a list of all known perfect numbers see the related link.
The factors of 420 are: 1,2,3,4,5,6,7,10,12,14,15,28,30,35,42,60,70,84,105,140,210,420
Factors are numbers you can multiply together to get another number. Therefore, all the factors of 21 are as follows: 1,3,7,21.
All Factors of 142:1, 2, 71, 142
It is the sum of all its factors (other than itself).
Yes, as has been known since 1588 For a list of all known perfect numbers see the related link.
496, 8128, 33550336, 8589869056, 137438691328, 2305843008139952128
28 is a perfect number. Add the factors of the number, excluding the number itself. 28: 1 +2 +4 + 7 + 14 = 28. The sum of its factors is the same as the number! The next perfect numbers are 496, 8128, 33550336, 8589869056, 137438691328, 2305843008139952128, 2658455991569831744654692615953842176, and 191561942608236107294793378084303638130997321548169216. Chances are that you won't be using that!
1, 2, 4, 7, 8, 14, 28, 56 1, 5, 17, 85 1, 2, 43, 86 1, 89 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90
No it is not. Here is a lits of some of the first perfect numbers6, 28, 496, 8128, 33550336, 8589869056, 137438691328, 2305843008139952128, 2658455991569831744654692615953842176, 191561942608236107294793378084303638130997321548169216
Yes, all the factors of 12 are factors of 24.
18 and all factors of 18. 18 and all factors of 18. 18 and all factors of 18. 18 and all factors of 18.
All the factors are 1.
No.
All of the factors of A.
Once all the prime factors of a number have been found, the number of factors the number has and what they are can be found. I'd be finding the prime factors first before finding all the factors of a number, so I'd rather find all the prime factors as it means I can stop before I have to do more work in finding all the factors.