Is 2781 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 2781 is composite or not first we have to find its factors.
Contents
Factors of 2781:
- If we have taken numbers from 1, 2, 3…for checking factors of 2781, we found that 2781 has factors 1, 3, 9, 27, 103, 309, 927 and 2781. Hence, we must say that 2781 is a composite number.
- Thus, 2781 is the composite number.
- If we multiply 2781 by 1, 2, 3 then we get the multiples of 2781 which are 2781, 5562 and so on.
2781 is a Composite number or Prime number
About the number 2781:
- 2781 has more than two factors which are 1, 3, 9, 27, 103, 309, 927 and 2781 and hence it is the composite number.
- 2781 is the odd composite number and it is not the perfect square also.
- If we divide 2781 by 1, 3, 9, 27, 103, 309, 927 and 2781 then we get remainder as zero. Hence 1, 3, 9, 27, 103, 309, 927 and 2781 are the factors of 2781
Note:
- 2781 is not the perfect square.
- Factors of 2781: 1, 3, 9, 27, 103, 309, 927 and 2781
- Prime factors of 2781: 3, 103
Conclusion:
- 2781 is the composite number which has factors 1, 3, 9, 27, 103, 309, 927 and 2781.
- And hence, 2781 is not the prime number.
Multiple Choice Questions:
1) 2781 is a
a) odd number
b) Prime number
c) even number
d) Both a and c
Ans: a) odd number
2) The non-prime factors of a composite number 2781 are
a) 1
b) 3, 103
c) 1, 3, 9, 27, 103, 309, 927 and 2781
d) 1, 9, 27, 309, 927 and 2781
Ans: d) 1, 9, 27, 309, 927 and 2781
3) 2781 is the odd composite number because
a) It has factors 1, 3, 9, 27, 103, 309, 927 and 2781
b) It has more than two factors
c) It is not divisible by 2
d) all
Ans: d) all