Salutare !!
[tex]\bf 45\cdot 45\cdot45\cdot45\cdot45\cdot45\cdot 45 =[/tex]
[tex]\bf 45^{7} =\bf 5^{7}\cdot 9^{7} = 78.125 \cdot 4.782.969 = \boxed{\bf 373. 669. 453. 125}[/tex]