The CAS Registry Mumber 73732-06-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,3,7,3 and 2 respectively; the second part has 2 digits, 0 and 6 respectively. Calculate Digit Verification of CAS Registry Number 73732-06: (7*7)+(6*3)+(5*7)+(4*3)+(3*2)+(2*0)+(1*6)=126 126 % 10 = 6 So 73732-06-6 is a valid CAS Registry Number.