The CAS Registry Mumber 19455-04-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,9,4,5 and 5 respectively; the second part has 2 digits, 0 and 4 respectively. Calculate Digit Verification of CAS Registry Number 19455-04: (7*1)+(6*9)+(5*4)+(4*5)+(3*5)+(2*0)+(1*4)=120 120 % 10 = 0 So 19455-04-0 is a valid CAS Registry Number.