The CAS Registry Mumber 78097-60-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,8,0,9 and 7 respectively; the second part has 2 digits, 6 and 0 respectively. Calculate Digit Verification of CAS Registry Number 78097-60: (7*7)+(6*8)+(5*0)+(4*9)+(3*7)+(2*6)+(1*0)=166 166 % 10 = 6 So 78097-60-6 is a valid CAS Registry Number.