The CAS Registry Mumber 124867-37-4 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,2,4,8,6 and 7 respectively; the second part has 2 digits, 3 and 7 respectively. Calculate Digit Verification of CAS Registry Number 124867-37: (8*1)+(7*2)+(6*4)+(5*8)+(4*6)+(3*7)+(2*3)+(1*7)=144 144 % 10 = 4 So 124867-37-4 is a valid CAS Registry Number.