What are the factors of $\aleph_0$?

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Extend the system of positive natural numbers with $\aleph_0$. Then we have:

$$\aleph_0 = \aleph_0\cdot n,\quad \forall n \in \mathbb{N}^+$$

Does it make sense to talk about factors of $\aleph_0$? What are the factors of $\aleph_0$?

Aside: Are there systems of numbers where it makes sense to talk about factors of infinite numbers?

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No. Cardinals are not suitable for talking about decomposition and factors.

The reason is that $\kappa\cdot\lambda=\max\{\kappa,\lambda\}$. So no cardinal can be expressed as "nontrivial" finite products of smaller cardinals. For infinite products we cannot really prove much in $\sf ZFC$.