RSA key pair has three parts: modulus \(n\) , encryption key exponent \(e\), decryption key exponent \(d\). Plain text is an unsigned integer \(m\), not larger than modulus and Cipher text is also an unsigned integer \(c\).
In Encryption,:
\[c = m^{e} \mod{n}\]
In Decryption we have:
\[m = c^{d} \mod{n}\]