21901-20-2 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 21901-20-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,1,9,0 and 1 respectively; the second part has 2 digits, 2 and 0 respectively.
Calculate Digit Verification of CAS Registry Number 21901-20:
(7*2)+(6*1)+(5*9)+(4*0)+(3*1)+(2*2)+(1*0)=72
72 % 10 = 2
So 21901-20-2 is a valid CAS Registry Number.