66521-81-1 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 66521-81-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,6,5,2 and 1 respectively; the second part has 2 digits, 8 and 1 respectively.
Calculate Digit Verification of CAS Registry Number 66521-81:
(7*6)+(6*6)+(5*5)+(4*2)+(3*1)+(2*8)+(1*1)=131
131 % 10 = 1
So 66521-81-1 is a valid CAS Registry Number.