33,550,336/Historical Note

Historical Note on $33 \, 550 \, 336$
The earliest record of the perfect nature of $33 \, 550 \, 336$ is in a medieval manuscript dating from $1456$.

When demonstrated in $1536$ that both $511 = 2^9 - 1$ and $2047 = 2^{11} - 1$ are composite, it was confirmed as being the $5$th perfect number.