Is 2121 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 2121 is composite or not first we have to find its factors.
Factors of 2121:
- If we have taken numbers from 1, 2, 3…for checking factors of 2121, we found that 2121 has factors 1, 3, 7, 21, 101, 303, 707 and 2121. Hence, we must say that 2121 is a composite number.
- Thus, 2121 is the composite number.
- If we multiply 2121 by 1, 2, 3 then we get the multiples of 2121 which are 2121, 4242 and so on.
2121 is a Composite number or Prime number
About the number 2121:
- 2121 has more than two factors which are 1, 3, 7, 21, 101, 303, 707 and 2121 and hence it is the composite number.
- 2121 is the odd composite number and it is not the perfect square also.
- If we divide 2121 by 1, 3, 7, 21, 101, 303, 707 and 2121 then we get remainder as zero. Hence, 1, 3, 7, 21, 101, 303, 707 and 2121 are the factors of 2121
Note:
- 2121 is not the perfect square.
- Factors of 2121: 1, 3, 7, 21, 101, 303, 707 and 2121
- Prime factors of 2121: 3, 7, 101
Conclusion:
- 2121 is the composite number which has factors 1, 3, 7, 21, 101, 303, 707 and 2121.
- And hence, 2121 is not the prime number.
Multiple Choice Questions:
1) 2121 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 2121 are
a) 1
b) 3, 7, 101
c) 1 and 2121
d) 1, 3, 7, 21, 101, 303, 707 and 2121
Ans: b) 3, 7, 101
3) 2121 is the composite number because
a) It has factors 1, 3, 7, 21, 101, 303, 707 and 2121
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
