If all the cells in question contain 4 digit numbers, then:

1 enter 20000 in an un-used cell
2 copy the cell
3 select the cells you want to change
4 edit / paste / special / with the addition button checked

if the cells do not contain 4 digit numbers, then do not use this method.
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Gary's Student


"Chirag Dedhia" wrote:

For ex: if the Value in the Cell is "3456" i want to change that to "23456".
Similarly every cell should be prefixed with "2"