Is 1785 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 1785 is composite or not first we have to find its factors.
Contents
Factors of 1785:
- If we have taken numbers from 1, 2, 3…for checking factors of 1785, we found that 1785 has factors 1, 3, 5, 7, 15, 17, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785. Hence, we must say that 1785 is a composite number.
- Thus, 1785 is the composite number.
- If we multiply 1785 by 1, 2, 3 then we get the multiples of 1785 which are 1785, 3570 and so on.
1785 is a Composite number or Prime number
About the number 1785:
- 1785 has more than two factors which are 1, 3, 5, 7, 15, 17, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785 and hence it is the composite number.
- 1785 is the odd composite number and it is not the perfect square also.
- If we divide 1785 by 1, 3, 5, 7, 15, 17, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785 then we get remainder as zero. Hence, 1, 3, 5, 7, 15, 17, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785 are the factors of 1785
Note:
- 1785 is not the perfect square.
- Factors of 1785: 1, 3, 5, 7, 15, 17, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785
- Prime factors of 1785: 3, 5, 7, 17
Conclusion:
- 1785 is the composite number which has factors 1, 3, 5, 7, 15, 17, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785.
- And hence, 1785 is not the prime number.
Multiple Choice Questions:
1) 1785 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 1785 are
a) 1
b) 3, 5, 7, 17
c) 1, 15, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785
d) 1, 3, 5, 7, 15, 17, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785
Ans: b) 1, 15, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785
3) 1785 is the odd composite number because
a) It has factors 1, 3, 5, 7, 15, 17, 21, 35, 51, 85, 105, 119, 255, 357, 595 and 1785
b) It has more than two factors
c) It is not divisible by 2
d) all
Ans: d) all