Celebrate a milestone birthday with a touch of mathematical humor! This black t-shirt features a playful design with a square root symbol over the number 6400, followed by "years old." The design also includes other math equations creating a smart and clever look. This tee makes a statement and is perfect for someone who loves mathematics or has a great sense of humor. Made from a comfortable material, it's ideal for casual wear at birthday parties, family gatherings, or everyday outings. A fun and unique way to acknowledge the big 8-0!