The CAS Registry Mumber 40469-13-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 4,0,4,6 and 9 respectively; the second part has 2 digits, 1 and 3 respectively. Calculate Digit Verification of CAS Registry Number 40469-13: (7*4)+(6*0)+(5*4)+(4*6)+(3*9)+(2*1)+(1*3)=104 104 % 10 = 4 So 40469-13-4 is a valid CAS Registry Number.