is the number 217 prime?
回答 (7)
2008-12-12 7:44 am
✔ 最佳答案
Prime is a whole number that has exactly two factors, 1 and itself.The first few primes are 2, 3, 5 and 7.
217 is not a prime as it has more than two factors: 1, 217, 31 and 7 = 4 factors
Therefore, since it has more than two factors, it is called a composite number.
參考: The one and only me
2008-12-12 3:56 pm
No.
It can be divided by 7.
It can be divided by 7.
2008-12-12 3:38 pm
no, if you divide by 7 it is 31
2008-12-12 6:13 pm
217 = 1 x 217
217 = 7 x 31
217 can be divided by 4 number completely, so it is a composite number.
217 = 7 x 31
217 can be divided by 4 number completely, so it is a composite number.
2008-12-12 4:23 pm
No. Any prime number that is one greater then a multiple of 4 can be expressed as the sum of 2 square numbers in exactly one way. 217 is one greater than a multiple of 4, yet cannot be so expressed.
參考: program written for calculator
2008-12-12 3:41 pm
217^1/2=14.73
2,3,5,7,11,13
217/7=31 NO,because 31 x 7=217
2,3,5,7,11,13
217/7=31 NO,because 31 x 7=217
2008-12-12 3:39 pm
Nope
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