Usually, the number has 3 digits. E numbers between E100 and E199 are colors. E numbers between E200 and E299 are preservatives. E numbers between E300 and E399 are antioxidants and acidity regulators. E numbers between E400 and E499 are thickeners, stabilizers and emulsifiers. E numbers between E500 and E599 are pH regulators. E numbers between E600 and E699 are flavor enhancers. E numbers between E700 and E799 are antibiotics. E numbers between E900 and E999 are glazing agents, gases, and sweeteners.