REPLACEB (old_text, start_num, num_bytes, new_text) The REPLACE and REPLACEB function syntax has the following arguments: Old_text Required. Text in which you want to replace some characters. Start_num Required. The position of the character in old_text that you want to replace with new_text. Num_chars Required. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.