Is 1280 is a composite number or not ?
- As we already know that, the number having factors 1 and the number itself is the prime number.
- And numbers having more than these two factors are the composite numbers.
- To check whether the number 1280 is composite or not first we have to find its factors.
Contents
Factors of 1280:
- If we have taken numbers from 1, 2, 3…for checking factors of 1280, we found that 1280 has factors 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280. Hence, we must say that 1280 is a composite number.
- Thus, 1280 is the composite number.
- If we multiply 1280 by 1, 2, 3 then we get the multiples of 1280 which are 1280, 2560 and so on.
About the number 1280:
- 1280 has more than two factors which are 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280 and hence it is the composite number.
- 1280 is the even composite number and it is not the perfect square also.
- If we divide 1280 by 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280 then we get remainder as zero. Hence, 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280 are the factors of 1280.
Note:
- 1280 is not the perfect square.
- Factors of 1280: 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280
- Prime factors of 1280: 2, 5
Conclusion:
- 1280 is the composite number which has factors 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280
- And hence, 1280 is not the prime number.
Multiple Choice Questions:
1) 1280 is a
a) Even number
b) Not a perfect square number
c) Composite number
d) all
Ans: d) all
2) The composite factors of a composite number 1280 are
a) 4, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280
b) 2, 5
c) 1, 4, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280
d) 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280
Ans: a) 4, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280
3) 1280 is composite number because
a) It has factors 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 256, 320, 640 and 1280
b) It has more than two factors
c) Divisible by 2
d) Both a and b
Ans: d) both a and b