The CAS Registry Mumber 144067-18-5 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,4,4,0,6 and 7 respectively; the second part has 2 digits, 1 and 8 respectively. Calculate Digit Verification of CAS Registry Number 144067-18: (8*1)+(7*4)+(6*4)+(5*0)+(4*6)+(3*7)+(2*1)+(1*8)=115 115 % 10 = 5 So 144067-18-5 is a valid CAS Registry Number.