In mathematics, RSA-220 is one of the RSA numbers, large semiprimes that are part of the RSA Factoring Challenge. RSA-220 has a length of 220 decimal digits and has not been factored so far.

RSA-220 = 2260138526203405784941654048610197513508038915719776718321197768109445641817 9666766085931213065825772506315628866769704480700018111497118630021124879281 99487482066070131066586646083327982803560379205391980139946496955261