The CAS Registry Mumber 82867-73-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,2,8,6 and 7 respectively; the second part has 2 digits, 7 and 3 respectively. Calculate Digit Verification of CAS Registry Number 82867-73: (7*8)+(6*2)+(5*8)+(4*6)+(3*7)+(2*7)+(1*3)=170 170 % 10 = 0 So 82867-73-0 is a valid CAS Registry Number.