Which of the following functions is not related to counting cells in Excel?

In the context of counting cells in Excel, the function that does not relate to this task is the SUM function. The SUM function is specifically designed to add together all the numerical values in a specified range of cells. Its primary purpose is numerical aggregation, rather than counting cells based on specific criteria.

On the other hand, functions like COUNT, COUNTA, and COUNTIF serve specific roles in counting cells. COUNT counts only the cells that contain numerical data, COUNTA counts all non-empty cells regardless of the type of data (including numbers, text, and errors), while COUNTIF counts cells that meet a specified condition or criteria. Therefore, these functions are closely related to the counting of cells, making SUM the outlier when considering counting tasks.