The CAS Registry Mumber 1397196-59-6 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,3,9,7,1,9 and 6 respectively; the second part has 2 digits, 5 and 9 respectively. Calculate Digit Verification of CAS Registry Number 1397196-59: (9*1)+(8*3)+(7*9)+(6*7)+(5*1)+(4*9)+(3*6)+(2*5)+(1*9)=216 216 % 10 = 6 So 1397196-59-6 is a valid CAS Registry Number.