The CAS Registry Mumber 82464-17-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,2,4,6 and 4 respectively; the second part has 2 digits, 1 and 7 respectively. Calculate Digit Verification of CAS Registry Number 82464-17: (7*8)+(6*2)+(5*4)+(4*6)+(3*4)+(2*1)+(1*7)=133 133 % 10 = 3 So 82464-17-3 is a valid CAS Registry Number.