Code point
U+222C
Glyph appearance depends on your fonts.
U+222C
Sm<compat> 222B 222BU+222C DOUBLE INTEGRAL is a Unicode 16.0.0 character in the Math Symbol category. It belongs to the Mathematical Operators block.
Choose the representation you need, then copy its value.
U+222C
8748
∬
∬
∬
E2 88 AC
222C
0000222C
%E2%88%AC
\u222C
\u222C
\u222C
\222C