The CAS Registry Mumber 1309869-67-7 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,3,0,9,8,6 and 9 respectively; the second part has 2 digits, 6 and 7 respectively. Calculate Digit Verification of CAS Registry Number 1309869-67: (9*1)+(8*3)+(7*0)+(6*9)+(5*8)+(4*6)+(3*9)+(2*6)+(1*7)=197 197 % 10 = 7 So 1309869-67-7 is a valid CAS Registry Number.