[raverbashing]

Factoring is not NP-hard (fixed!), it's simpler than that (but not, until the present day, P)

It is NP though (edited as per child comment)

[amalcon]

It is NP (well, it would be if it were a decision problem). It is not (known to be) NP-complete (or, equivalently since it is NP, NP-hard).

[raverbashing]

Ah true, my mistake, it is not NP-hard but it is in NP

Wikipedia says it's UP https://en.wikipedia.org/wiki/UP_%28complexity%29 (which is contained in NP)