Is 1645 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 1645 is composite or not first we have to find its factors.
Contents
Factors of 1645:
- If we have taken numbers from 1, 2, 3…for checking factors of 1645, we found that 1645 has factors 1, 5, 7, 35, 47, 235, 329 and 1645. Hence, we must say that 1645 is a composite number.
- Thus, 1645 is the composite number.
- If we multiply 1645 by 1, 2, 3 then we get the multiples of 1645 which are 1645, 3290 and so on.
1645 is a Composite number or Prime number
About the number 1645:
- 1645 has more than two factors which are 1, 5, 7, 35, 47, 235, 329 and 1645 and hence it is the composite number.
- 1645 is the odd composite number and it is not the perfect square also.
- If we divide 1645 by 1, 5, 7, 35, 47, 235, 329 and 1645 then we get remainder as zero. Hence, 1, 5, 7, 35, 47, 235, 329 and 1645 are the factors of 1645
Note:
- 1645 is not the perfect square.
- Factors of 1645: 1, 5, 7, 35, 47, 235, 329 and 1645
- Prime factors of 1645: 5, 7, 47
Conclusion:
- 1645 is the composite number which has factors 1, 5, 7, 35, 47, 235, 329 and 1645.
- And hence, 1645 is not the prime number.
Multiple Choice Questions:
1) 1645 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 1645 are
a) 1
b) 5, 7, 47
c) 1, 35, 235, 329and 1645
d) 1, 5, 7, 35, 47, 235, 329 and 1645
Ans: b) 1, 35, 235, 329 and 1645
3) 1645 is the odd composite number because
a) It has factors 1, 5, 7, 35, 47, 235, 329 and 1645
b) It has more than two factors
c) It is not divisible by 2
d) all
Ans: d) all