Find the HCF of 80 and 567 ?

80 = 1$\times$2$\times$2$\times$2$\times$2$\times$5 

567 = 1$\times$3$\times$3$\times$3$\times$3$\times$7. The largest common factor between the two numbers is 1. 

Using Euclid's Division lemma

567=80$\times$7+7

80=7$\times$11+3

7=3$\times$2+1

3=1$\times$3+0

1 is the HCF