How can the sum of digits of a multiple of 2016 equal 2016?

In summary, the question is asking for the least multiple of 2016 that has a digit sum of 2016. It is determined that the answer must have 225 digits, with the last digit being 8. This is because the least number of digits required to get a digit sum of 2016 is 224, but a string of only 9s is not divisible by 2016, so an extra digit is needed. The answer is found to be $5989\overbrace{\ldots}^{\text {217 9s}}989888$, which is shorter than the example given. The explanation for this answer is provided in the source given.
  • #1
vidyarth
17
0
What is the least multiple of 2016 such that the sum of its digits is 2016.
I think the answer must be a 225 digit long number ending in 8 but do not know the exact value nor how to prove it. Any ideas. Thanks beforehand.
 
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  • #2
Hi vidyarth and welcome to MHB! :D

vidyarth said:
I think the answer must be a 225 digit long number ending in 8 ...

Why?
 
  • #3
greg1313 said:
Hi vidyarth and welcome to MHB! :D
Why?

This is because the least number of digits required to get a digit sum of $2016$ is $\frac{2016}{9}=224$. But since a string consisting of only $9$s is not divisible by $2016$, therefore it can be made up by using one extra digit. And I think the number should end in $8$ which is the second maximum digit.
 
  • #4
I get 223 followed by 221 9's followed by 776.
 
  • #6
vidyarth said:
The answer found ... is $5989\overbrace{\ldots}^{\text {217 9s}}989888$

That should be $598\overbrace{9\ldots9}^{\text{217 9s}}89888$
 
  • #7
greg1313 said:
That should be $598\overbrace{9\ldots9}^{\text{217 9s}}89888$

yes. But can you explain how you get it, thoroughly?
 

FAQ: How can the sum of digits of a multiple of 2016 equal 2016?

What does "Property of multiple of 2016" mean?

The property of multiple of 2016 refers to a specific characteristic or quality shared by any number that is a multiple of 2016. This means that any number that is divisible by 2016 will have this property.

What is the significance of "2016" in this property?

The number 2016 is significant in this property because it is the smallest number that is divisible by all numbers from 1 to 12. This makes it a highly composite number and gives it unique properties.

How do you determine if a number is a multiple of 2016?

To determine if a number is a multiple of 2016, you can use the divisibility rules for 2016. These rules state that a number is a multiple of 2016 if it is divisible by 2, 3, 4, 6, 7, 8, 9, 12, 14, 16, 18, 21, 24, 28, 32, 36, 42, 48, 56, 63, 72, 84, 96, 112, 126, 144, 168, 192, 224, 252, 288, 336, 384, 448, 504, 576, 672, 756, 864, 1008, 1152, 1344, 1512, 1728, or 2016.

What are some practical applications of this property?

This property can be useful in many real-world applications, particularly in mathematics and engineering. For example, it can be used in calculating least common multiples and in finding efficient ways to distribute resources evenly among a large number of people or objects.

Are there any other numbers with similar properties?

Yes, there are other numbers with similar properties to 2016. These include highly composite numbers such as 2520, 27720, and 720720. These numbers are also divisible by a large number of smaller numbers and have unique mathematical properties.

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