Results so far. Here are the (up to) 10 largest factors (of at least 60 digits) found by ECM so far in 2021 (see also the all-times top-50 table, and the top ten from 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020):
| digits | factor | from | B1 | sigma | date | who |
| 70 | 4702574864356903668328925230483249938419748952832641483390255334999479 | 5493-1 | 13e8 | 1:3612551401 | 04 Jan 2021 | S. Wagstaff |
| 69 | 457309376061341968858969907539927424797564127673204762828701146483601 | 22390+1 | 16e8 | 1:195128836 | 09 Jan 2021 | S. Wagstaff |
| 66 | 159424401285021433633036984212552441813954559105788158682518270641 | 22822+1 | 14e8 | 1:191735519 | 03 Jan 2021 | S. Wagstaff |
| 64 | 5940231518639818133881548617394754356089382789141290697209920297 | 22978+1 | 9e8 | 1:472852269 | 01 Jan 2021 | S. Wagstaff |
| 64 | 1181944190217838168575602563426725286703053115907380051630816233 | 3823-1 | 13e8 | 1:241190710 | 06 Jan 2021 | S. Wagstaff |
| 62 | 65221813646259307849177925259144124430100794460972383852316997 | 22962+1 | 9e8 | 1:1575132975 | 15 Jan 2021 | S. Wagstaff |
| 62 | 12759074070386794629112979935583364791172819193489389442256711 | 960*3960-1 | 7e8 | 1:216455167 | 05 Jan 2021 | S. Wagstaff |
| 61 | 4271913531347872661417285099994612159045193616787632359109141 | 22810+1 | 23e8 | 1:3745117987 | 02 Jan 2021 | S. Wagstaff |
| 61 | 1162557396592890801376548182666168711447381651683632151567501 | 22790+1 | 25e8 | 1:3825050605 | 01 Jan 2021 | S. Wagstaff |
ECMNET Newsletters: number 1 (13 Feb 1998), number 2 (15 Mar 1998), number 3 (17 Apr 1998), number 4 (15 May 1998), number 5 (18 June 1998), number 6 (15 July 1998), number 7 (17 August 1998), number 8 (17 September 1998), number 9 (16 October 1998), number 10 (23 November 1998), number 11 (17 December 1998), number 12 (19 April 1999), number 13 (16 December 1999).
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