Sum cells that are not errors

The SUM function does not return a sum if any of the cells contain errors. You can use "=SUMIF("A2:A10",<>"#VALUE!")".
{=SUM(IF(ISERROR(CellRange),"",CellRange))} = 623

Built-in Functions

SUM - The total of the numerical values.
IF - The value based on whether a condition is True or False.
ISERROR - The boolean True or False depending if the value is an error.
SUMIF - (SUMIFS) The total of the numerical values that satisfies one condition.