The previous record was 2

The previous record was RSA-155 (22 August 1999) with 512 bits (155 digits).

The previous record was RSA-140 (2 February 1999).

The previous record was RSA-130 (10 April 1996) with 130 digits.

The previous revord was RSA129, which was factored using the Multiple Polynomial Quadratic Sieve (MPQS) from August 1993 to April 1994 by a "factor-by-mail" project, using about 5000 mips years, 600 volunteers from more than 20 countries, on all continents except Antarctica. The two factors have 64 and 65 digits.

**ECM.**
The previous record was
66 digits,
found by B. Dodson on April 6, 2005.
The previous record was 59 digits (10^{233}-1)
found by B. Dodson on February 20, 2005.
The previous record was 58 digits (8*10^{141}-1),
found by R. Backstrom on November 1st, 2003
(however with a p52 cofactor, thus it could have been found by NFS, thus this
record was not taken into account in Richard Brent champions list).
The previous record was 57 digits (2^{997}-1),
found by B. Dodson on 21st June 2003.
The previous record was 55 digits (93^{56}+56^{93})
found by P. Gaudry on 13 December 2002.
The previous record was 54 digits
[(6^43-1)^42+1, factored by Nik Lygeros and Michel Mizony on December 26,
1999].
The previous records were:
a p53 factor from 2^677-1 c150 found by Conrad Curry on September 14, 1998;
a p49 factor from 2^1071+1 c132 found by Paul Zimmermann on June 19, 1998;
a p48 factor from 24^121+1 c130 found by Richard P. Brent on October 9, 1997;
a p47 factor from 30^109-1 c89 found by Peter Montgomery on February 25, 1996
(however from a c89, thus not taken into account in Richard Brent champions
list);
a p47 factor from 5^256+1 c134 found by Peter Montgomery on November 27, 1995;
a p44 factor from p(19069) c99 found by Berger-Mueller on June 21, 1995;
a p43 factor from p(19997) c139 found by Berger-Mueller on March 20, 1993;
a p42 factor from 10^201-1 c111 found by D. Rusin on April 5, 1992;
a p40 factor from p(11279) c89 found by Lenstra-Dixon on October 28, 1991
(graphical representation).
See
a description of the algorithm(s).

**Special Numbers.**
The previous record was
248 digits, with 2,1642M factored by Aoki/Kida/Shimoyama/Sonoda/Ueda (CRYPTREC)
on April 04, 2004.
The previous record was
244 digits, with 2^{809}-1 factored by Franke/Kleinjung/Bahr/CWI
on January 3, 2003.
The previous record was
233 digits for the special number field sieve or SNFS (
2^773+1 by The
Cabal in November 2000).