The CAS Registry Mumber 32116-96-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,2,1,1 and 6 respectively; the second part has 2 digits, 9 and 6 respectively. Calculate Digit Verification of CAS Registry Number 32116-96: (7*3)+(6*2)+(5*1)+(4*1)+(3*6)+(2*9)+(1*6)=84 84 % 10 = 4 So 32116-96-4 is a valid CAS Registry Number.