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							|  |  |  |  | id: 5900f4151000cf542c50ff27 | 
					
						
							|  |  |  |  | title: 'Problem 168: Number Rotations' | 
					
						
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										 |  |  |  | challengeType: 5 | 
					
						
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										 |  |  |  | forumTopicId: 301802 | 
					
						
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										 |  |  |  | dashedName: problem-168-number-rotations | 
					
						
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										 |  |  |  | # --description--
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										 |  |  |  | Consider the number 142857. We can right-rotate this number by moving the last digit (7) to the front of it, giving us 714285. | 
					
						
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										 |  |  |  | It can be verified that $714285 = 5 × 142857$. | 
					
						
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										 |  |  |  | This demonstrates an unusual property of 142857: it is a divisor of its right-rotation. | 
					
						
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										 |  |  |  | Find the last 5 digits of the sum of all integers $n$, $10 < n < 10100$, that have this property. | 
					
						
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										 |  |  |  | # --hints--
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										 |  |  |  | `numberRotations()` should return `59206`. | 
					
						
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										 |  |  |  | ```js | 
					
						
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										 |  |  |  | assert.strictEqual(numberRotations(), 59206); | 
					
						
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										 |  |  |  | ``` | 
					
						
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										 |  |  |  | # --seed--
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										 |  |  |  | ## --seed-contents--
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							|  |  |  |  | ```js | 
					
						
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										 |  |  |  | function numberRotations() { | 
					
						
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										 |  |  |  |   return true; | 
					
						
							|  |  |  |  | } | 
					
						
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										 |  |  |  | numberRotations(); | 
					
						
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										 |  |  |  | ``` | 
					
						
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										 |  |  |  | # --solutions--
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | // solution required | 
					
						
							|  |  |  |  | ``` |