Is 819 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 819 is composite or not first we have to find its factors.
Contents
Factors of 819:
- If we have taken numbers from 1, 2, 3…for checking factors of 819, we found that 819 has factors 1, 3, 7, 9, 13, 21, 39, 63, 91, 117, 273 and 819. Hence, we must say that 819 is a composite number.
- Thus, 819 is the composite number.
- If we multiply 819 by 1, 2, 3 then we get the multiples of 819 which are 819, 1638 and so on.
819 is a Composite number or Prime number
About the number 819:
- 819 has more than two factors which are 1, 3, 7, 9, 13, 21, 39, 63, 91, 117, 273 and 819 and hence it is the composite number.
- 819 is the odd composite number and it is not the perfect square also.
- If we divide 819 by 1, 3, 7, 9, 13, 21, 39, 63, 91, 117, 273 and 819 then we get remainder as zero. Hence, 1, 3, 7, 9, 13, 21, 39, 63, 91, 117, 273 and 819 are the factors of 819
Note:
- 819 is not the perfect square.
- Factors of 819: 1, 3, 7, 9, 13, 21, 39, 63, 91, 117, 273 and 819
- Prime factors of 819: 3, 7, 13
Conclusion:
- 819 is the composite number which has factors 1, 3, 7, 9, 13, 21, 39, 63, 91, 117, 273 and 819.
- And hence, 819 is not the prime number.
Multiple Choice Questions:
1) 819 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 819 are
a) 1
b) 3, 7, 13
c) 1, 9, 21, 39, 63, 91, 117, 273 and 819
d) 1, 3, 7, 9, 13, 21, 39, 63, 91, 117, 273 and 819
Ans: b) 3, 7, 13
3) 819 is the odd composite number because
a) It has factors 1, 3, 7, 9, 13, 21, 39, 63, 91, 117, 273 and 819
b) It is divisible by 2
c) It is not divisible by 2
d) Both a and c
Ans: d) both a and c