Is 1420 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 1420 is composite or not first we have to find its factors.
Contents
Factors of 1420:
- If we have taken numbers from 1, 2, 3…for checking factors of 1420, we found that 1420 has factors 1, 2, 4, 5, 10, 20, 71, 142, 284, 355, 710 and 1420. Hence, we must say that 1420 is a composite number.
- Thus, 1420 is the composite number.
- If we multiply 1420 by 1, 2, 3 then we get the multiples of 1420 which are 1420, 2840 and so on.
About the number 1420:
- 1420 has more than two factors which are 1, 2, 4, 5, 10, 20, 71, 142, 284, 355, 710 and 1420 and hence it is the composite number.
- 1420 is the even composite number and it is not the perfect square also.
- If we divide 1420 by 1, 2, 4, 5, 10, 20, 71, 142, 284, 355, 710 and 1420 then we get remainder as zero. Hence, 1, 2, 4, 5, 10, 20, 71, 142, 284, 355, 710 and 1420 are the factors of 1420.
Note:
- 1420 is not the perfect square.
- Factors of 1420: 1, 2, 4, 5, 10, 20, 71, 142, 284, 355, 710 and 1420
- Prime factors of 1420: 2, 5, 71
Conclusion:
- 1420 is the composite number which has factors 1, 2, 4, 5, 10, 20, 71, 142, 284, 355, 710 and 1420
- And hence, 1420 is not the prime number.
Multiple Choice Questions:
1) 1420 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 1420 are
a) 4, 10, 20, 142, 284, 355, 710 and 1420
b) 2, 5, 71
c) 1, 4, 10, 20, 142, 284, 355, 710 and 1420
d) 1, 2, 4, 5, 10, 20, 71, 142, 284, 355, 710 and 1420
Ans: a) 4, 10, 20, 142, 284, 355, 710 and 1420
3) 1420 is composite number because
a) It has factors 1, 2, 4, 5, 10, 20, 71, 142, 284, 355, 710 and 1420
b) It has more than two factors
c) Divisible by 2
d) Both a and b
Ans: d) both a and b