yogi_Compute Sigma Code Of Numerals In A String

Yogi Anand, D.Eng, P.E.                                         Google Spreadsheet                            www.energyefficientbuild.com

sigma code of a numeral in a single cell
is there a way to add the numerals in a number in a single cell?
For example, I have the number 2,345. I'd like to add the individual numbers together: 2+3+4+5=14
THEN take that '14' and get 1+4 =5.
I'm taking large numbers generated by my spreadsheet and getting their sigma codes to do a little prime number research
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