The CAS Registry Mumber 61419-61-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,1,4,1 and 9 respectively; the second part has 2 digits, 6 and 1 respectively. Calculate Digit Verification of CAS Registry Number 61419-61: (7*6)+(6*1)+(5*4)+(4*1)+(3*9)+(2*6)+(1*1)=112 112 % 10 = 2 So 61419-61-2 is a valid CAS Registry Number.