Excel spreadsheets display a series of number or pound signs like ##### in a cell when the column isn’t big enough to display the information. It also happens if you have a cell formatted to display something different than what you need the spreadsheet to show. All versions of Excel do this, and most formulas in Excel are the same regardless of the version used.
TL;DR (Too Long; Didn't Read)
The quickest and easiest way to fix the problem is to move the mouse cursor to the header where the individual letters appear for each column. On the right edge of the column, in which the cell sits, hover the cursor until it turns into a plus sign with arrows on each end of the horizontal bar. Click the left button on a right hand-driven mouse and hold it and move the column’s edge to resize the column and cell for the width needed.
Too Small of a Cell
Excel allows users to manage options to adapt its layout to suit your needs. If one or more spreadsheet cells are too narrow, you can resize them. If you resize a cell that contains numbers, it may display ##### if you make it too narrow. This happens only if it sits to the left of another cell that contains content. This can also occur if you copy a number into a cell too narrow to display the number.
Numbers Gone Missing
Even though number signs may appear in a cell, Excel still knows the cell's real value and displays it in the spreadsheet's formula bar. If many cells in the spreadsheet contain number signs, click them individually and note their values in that bar. Hold the cursor over a cell to display a pop-up tool tip that shows the cell's real numerical value.
Widen the Cells
Make the problem go away by clicking the column’s right edge in the header area, holding down the left mouse button and dragging your cursor to the right until the cell’s number appears. You could also select the cells you’d like to resize, click “Home” and then click the ribbon's “Format” tab. Click the “AutoFit Column Width” menu option and Excel resizes the cells so that their content fits within them and the number signs disappear.
When the Problem Occurs
If you type regular text into cells, you won’t have this problem because Excel does not replace the text with number signs. You usually won’t see number signs when you first type a large number into a cell that’s too narrow because Excel makes the cell wider to fit the value. Number signs appear when you paste a large number from another cell or make an existing cell’s width smaller.
The pound or number signs may also appear if a cell has a formula that generates a negative number. If the column or cell is formatted to display a date and you input a large number, it will also display the pound symbols. Check cell formatting by selecting a cell and clicking the right mouse button. A pop-up menu appears: click “Format Cell” near the bottom. In the menu that appears, select thee “Number” tab, and then choose the number format desired.