The RSA algorithm works because, when n is sufficiently large, deriving d from a known e and n will be an impractically long calculation — unless we know p, in which case we can use the shortcut ...

A quantum computer with a million qubits would be able to crack the vital RSA encryption algorithm, and while such machines don't yet exist, that estimate could still fall further ...

But most modern encryption technologies now use 1024- to 2048-bit integers. A 1024-bit integer has 1.797 x 10^308 possible values, while a 2048-bit integer has 3.231 x 10^616 possible values.

RSA is a public-key encryption algorithm used to encrypt and decrypt data. It relies on two different but linked keys: a public key for encryption and a private key for decryption.