Is riboflavin water or fat-soluble

Riboflavin is more commonly known as vitamin B2. B and C vitamins are known as the water soluble vitamins, compared to the A, D, E, K vitamins being soluble in fat. However, solubility of riboflavin in water is not very good. Solubility of 0.012% (12 mg in 100 mL water) is mentioned in scientific literature dating back to 1942.