# Create self signed certificate from modulus, private and public exponents of RSA

I have the values of RSA public exponent $$e$$, the secret exponent $$d$$ and the modulus $$n$$.

How can I create (for example using openssl) a self-signed certificate using the RSA key $$(n,d), (n,e)$$? Is it even possible?

Second question: Is it possible to get the factors of $$n$$ from $$(n,d), (n,e)$$?

• 2. $(n,d)$ in usually contains information about $p$ and $q$ so that the calculations can use CRT. – kelalaka Oct 29 '19 at 20:56

Yes, you can get the factors from this answer which is about calculating the CRT parameters, but those include the $$p$$ and $$q$$ values.