You can write rewrite 632 as follows:
[tex] 632 = 2 + 3\times 10 + 6 \times 100 [/tex]
So, you have
[tex] 512 \times 632 = 512 \times (2 + 3\times 10 + 6 \times 100) [/tex]
Which you can distribute as
[tex] 512 \times 2 + 512 \times 3\times 10 + 512 \times 6 \times 100 [/tex]
You can easily compute
[tex] 512 \times 2 = 1024,\quad 512 \times 3 = 1536,\quad 512\times 6 = 3072 [/tex]
So,
[tex] 512 \times 2 + 512 \times 3\times 10 + 512 \times 6 \times 100 = 1024 + 15360 + 307200 [/tex]
which gives 323584
