The CAS Registry Mumber 149456-48-4 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,4,9,4,5 and 6 respectively; the second part has 2 digits, 4 and 8 respectively. Calculate Digit Verification of CAS Registry Number 149456-48: (8*1)+(7*4)+(6*9)+(5*4)+(4*5)+(3*6)+(2*4)+(1*8)=164 164 % 10 = 4 So 149456-48-4 is a valid CAS Registry Number.