Excel stores numbers with a maximum precision of 15 significant digits. It cannot handle 16 digit numbers.
If the value is some kind of ID number, you probably don't have to perform calculations with it. If so, you can format the cell as text before entering the value, or prefix the value with an apostrophe ' to force it to be interpreted as text.
If you need to perform calculations with numbers of 16 or more digits, you'd need to install an add-in that provides this capability.