Is 639 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 639 is composite or not first we have to find its factors.
Contents
Factors of 639:
- If we have taken numbers from 1, 2, 3…for checking factors of 639, we found that 639 has factors 1, 3, 9, 71, 213 and 639. Hence, we must say that 639 is a composite number.
- Thus, 639 is the composite number.
- If we multiply 639 by 1, 2, 3 then we get the multiples of 639 which are 639, 1278 and so on.
639 is a Composite number or Prime number
About the number 639:
- 639 has more than two factors which are 1, 3, 9, 71, 213 and 639 and hence it is the composite number.
- 639 is the odd composite number and it is not the perfect square also.
- If we divide 639 by 1, 3, 9, 71, 213 and 639 then we get remainder as zero. Hence, 1, 3, 9, 71, 213 and 639 are the factors of 639.
Note:
- 639 is not the perfect square.
- Factors of 639: 1, 3, 9, 71, 213 and 639
- Prime factors of 639: 3, 71
Conclusion:
- 639 is the composite number which has factors 1, 3, 9, 71, 213 and 639.
- And hence, 639 is not the prime number.
Multiple Choice Questions:
1) 639 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 639 are
a) 1
b) 3, 71
c) 1, 9, 213 and 639
d) 1, 3, 9, 71, 213 and 639
Ans: b) 3, 71
3) 639 is the odd composite number because
a) It has factors 1, 3, 9, 71, 213 and 639
b) It is divisible by 2
c) It is not divisible by 2
d) Both a and c
Ans: d) both a an c