Is 1689 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 1689 is composite or not first we have to find its factors.
Contents
Factors of 1689:
- If we have taken numbers from 1, 2, 3…for checking factors of 1689, we found that 1689 has factors 1, 3, 563 and 1689. Hence, we must say that 1689 is a composite number.
- Thus, 1689 is the composite number.
- If we multiply 1689 by 1, 2, 3 then we get the multiples of 1689 which are 1689, 3378 and so on.
1689 is a Composite number or Prime number
About the number 1689:
- 1689 has more than two factors which are 1, 3, 563 and 1689 and hence it is the composite number.
- 1689 is the odd composite number and it is not the perfect square also.
- If we divide 1689 by 1, 3, 563 and 1689 then we get remainder as zero. Hence, 1, 3, 563 and 1689 are the factors of 1689
Note:
- 1689 is not the perfect square.
- Factors of 1689: 1, 3, 563 and 1689
- Prime factors of 1689: 3, 563
Conclusion:
- 1689 is the composite number which has factors 1, 3, 563 and 1689.
- And hence, 1689 is not the prime number.
Multiple Choice Questions:
1) 1689 is a
a) Even number
b) Prime number
c) Composite number
d) Both a and c
Ans: c) composite number
2) The non-prime factors of a composite number 1689 are
a) 1
b) 3, 563
c) 1 and 1689
d) 1, 3, 563 and 1689
Ans: b) 1 and 1689
3) 1689 is the odd composite number because
a) It has factors 1, 3, 563 and 1689
b) It has more than two factors
c) It is not divisible by 2
d) all
Ans: d) all