Tool to find the sum of all digits of a number. The digit sum of a number is often used in numerology and sometimes in math problems.
Sum of Digits - dCode
Tag(s) : Number Games, Arithmetics
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Sum of Digits
Digit Sum Calculator
Answers to Questions (FAQ)
What is the sum of digits in a number? (Definition)
The sum of the digits of a number is the addition of each digit composing a number.
A number is made up of digits. In the decimal base, there are 10 digits: 0,1,2,3,4,5,6,7,8 and 9.
How to calculate the sum of digits in a number?
The only method is to count the sum total of all digits, as does dCode.
Example: 123 $ 1+2+3 = 6 $
Pay attention to say sum of the digits of a number (the expressions such as the sum of a digit, or the sum of a number are meaningless)
How to calculate a digital root?
The digital root is computed through recursive reduction (repeated sum) that consists in repeating the addition operation until the result has only one digit.
Example: 789: $ 7+8+9 = 24 $ and $ 2+4 = 6 $
A mathematical formula makes it possible to calculate the numerical root $ r $ directly: $$ r(n) = n - 9 \left\lfloor \frac{n}{9} \right\rfloor $$
What is the difference between a number and a digit?
A number is made of digits, like a word is made of letters.
Example: There are only 10 digits: 0,1,2,3,4,5,6,7,8,9 (in base 10)
Example: There is an infinity of numbers
Numbers can have only one digit such as 1, 2 ou 3 (they are both numbers and digits)
Source code
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