U+1D7D9 MATHEMATICAL DOUBLE-STRUCK DIGIT ONE

The Unicode character U+1D7D9, officially named MATHEMATICAL DOUBLE-STRUCK DIGIT ONE, was introduced in Unicode version 3.1. It is part of the Math Alphanum block, which belongs to the Supplementary Multilingual plane.

Categorized technically as a Decimal Number, this character typically falls under the Common script. In terms of text layout and rendering, the glyph is Unknown and has no designated width in East Asian typography. When placed in bidirectional text, it behaves as an European Number character. Its visual representation remains not mirrored regardless of the reading direction.