The CAS Registry Mumber 112562-66-0 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,2,5,6 and 2 respectively; the second part has 2 digits, 6 and 6 respectively. Calculate Digit Verification of CAS Registry Number 112562-66: (8*1)+(7*1)+(6*2)+(5*5)+(4*6)+(3*2)+(2*6)+(1*6)=100 100 % 10 = 0 So 112562-66-0 is a valid CAS Registry Number.