=TEXT(value, format_text) returns the value as text, formatted with the same codes as the Format Cells dialog:
- dates:
"mmm" is Mar, "mmmm" is March, "yyyy" is 2026, "dddd" is Monday, "mmm d, yyyy" is Mar 2, 2026;
- numbers:
"0.0%", "$#,##0.00", "#,##0";
- leading zeros:
"00000" turns 42 into 00042.
Watch m and mm: on their own they're months, but after h they mean minutes.
The result is text, so it's for labels, joined sentences and grouping keys, not for further math. When you only want a cell to look different, change its number format instead and keep the number.