The CAS Registry Mumber 122097-67-0 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,2,2,0,9 and 7 respectively; the second part has 2 digits, 6 and 7 respectively. Calculate Digit Verification of CAS Registry Number 122097-67: (8*1)+(7*2)+(6*2)+(5*0)+(4*9)+(3*7)+(2*6)+(1*7)=110 110 % 10 = 0 So 122097-67-0 is a valid CAS Registry Number.