Arithmetic & Number Theory
Sum of Digits
Add all digits of an integer.
Formula
Formula
S = Σ di
Variables
| Symbol | Definition | Type & range | Units | Role |
|---|---|---|---|---|
| n | integer | integer (ℤ) | — | input |
| S | digit sum | computed result | — | result |
Try it yourself
Interactive calculator
Worked examples
Example 1
Givenn = 12345
Result15
Example 2
Givenn = 99999
Result45