If you use the cell it in certain functions, it performs the operation on the "100000" not the true value. Use the errant cell in FIXED and you 100000 for the answer [ =FIXED(A1,0,1) ]. FIXED transforms the number value to a text value; this must be more than a display error.
It seems many functions that treat the cell value as text use the errant value of 1000000 instead of the true value.
If you use the cell it in certain functions, it performs the operation on the "100000" not the true value. Use the errant cell in FIXED and you 100000 for the answer [ =FIXED(A1,0,1) ]. FIXED transforms the number value to a text value; this must be more than a display error. It seems many functions that treat the cell value as text use the errant value of 1000000 instead of the true value.