Is 2145 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 2145 is composite or not first we have to find its factors.
Contents
Factors of 2145:
- If we have taken numbers from 1, 2, 3…for checking factors of 2145, we found that 2145 has factors 1, 3, 5, 11, 13, 15, 33, 39, 55, 65, 143, 165, 195, 429, 715 and 2145. Hence, we must say that 2145 is a composite number.
- Thus, 2145 is the composite number.
- If we multiply 2145 by 1, 2, 3 then we get the multiples of 2145 which are 2145, 4290 and so on.
2145 is a Composite number or Prime number
About the number 2145:
- 2145 has more than two factors which are 1, 3, 5, 11, 13, 15, 33, 39, 55, 65, 143, 165, 195, 429, 715 and 2145 and hence it is the composite number.
- 2145 is the odd composite number and it is not the perfect square also.
- If we divide 2145 by 1, 3, 5, 11, 13, 15, 33, 39, 55, 65, 143, 165, 195, 429, 715 and 2145 then we get remainder as zero. Hence, 1, 3, 5, 11, 13, 15, 33, 39, 55, 65, 143, 165, 195, 429, 715 and 2145 are the factors of 2145
Note:
- 2145 is not the perfect square.
- Factors of 2145: 1, 3, 5, 11, 13, 15, 33, 39, 55, 65, 143, 165, 195, 429, 715 and 2145
- Prime factors of 2145: 3, 5, 11, 13
Conclusion:
- 2145 is the composite number which has factors 1, 3, 5, 11, 13, 15, 33, 39, 55, 65, 143, 165, 195, 429, 715 and 2145.
- And hence, 2145 is not the prime number.
Multiple Choice Questions:
1) 2145 is a
a) odd number
b) Prime number
c) Composite number
d) Both a and c
Ans: d) both a and c
2) The prime factors of a composite number 2145 are
a) 1
b) 3, 5, 11, 13
c) 1 and 2145
d) 1, 3, 5, 11, 13, 15, 33, 39, 55, 65, 143, 165, 195, 429, 715 and 2145
Ans: b) 3, 5, 11, 13
3) 2145 is the composite number because
a) It has factors 1, 3, 5, 11, 13, 15, 33, 39, 55, 65, 143, 165, 195, 429, 715 and 2145
b) It has more than two factors
c) It is not divisible by 2
d) Both a and b
Ans: d) both a and b