is 2 21055501 - 1
has 6338338 decimal digits
takes 14.922 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
factored, 0 LL tests remaining
ResidueStatus
L-LDCC7BA0B3AE74A0Adouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual274181.703966.2162%937000114612960065.07737.3276%246.781268.6917%
Target2695.670163.7681%150000360000002.16123.7852%7.831365.1396%
Difference+5+176.0338+2.4481%+787000+1110129600+62.9161+3.5423%+238.9499+3.5522%

Known prime factors (1 factor, 136.3 bits, 0.00064727% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2105550110614347139950067524750027684912550647340142136.2852520563899180092538465370091386700
22 × 33 × 52 × 7 × 13 × 17 × 23 × 383 × 1033 × 2251 × 39761 × 461323 × 1606123		2023-06-2446132316061236.374e+90.53810.9648

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2004-02-14ANONYMOUSv4_computers330000330000---0.339--1.028%
2023-06-24James Heinrich3930K937000114612960042136.28565.0829.84130.27.328%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2001-04-21ANONYMOUSv4_computers21256--0.000--
2002-11-09Donna Noblev4_computers21266--0.701--
2015-04-09NRManual testing266267--0.710--
2017-05-04ramgeisManual testing267268--1.420--
2017-09-15ramgeisManual testing268269--2.839--
2017-09-15ramgeisManual testing269270--5.679--
2021-09-14SRBaseManual testing270271--11.36--
2021-10-01-Anonymous-Manual testing271272--22.71--
2021-11-19-Anonymous-Manual testing272273--45.43--
2021-12-23-Anonymous-Manual testing273274--90.86--


ECM factoring results:
No ECM results for M21055501


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2004-02-23ANONYMOUSv4_computersDCC7BA0B3AE74A0A14.92
2008-10-04jbarchukv4_computersDCC7BA0B3AE74A0A14.92


PRP results:
dateuseridcompidcofactorsres64PRP
2023-08-07Max Dettweilerframework
106143471399500675247500276849125506473401
14D45515C47EF93Cno


P-1 factor-bounds graph:
B1 = 937000, B2 = 1146129600 (P-1 stage 2)
B1 = 937000 (P-1 stage 1)
B1 = 330000 (P-1 stage 1)
104
105
106
104
105
106
107
108
109
1010
TF factor-bounds graph:
274
273
272
271
270
269
268
267
266
256
this exponent TF target: 69
TF double-checked to: 67.9
250
260
270
280
290
2100
2110
2120
2130
2140
Last modified: 2023-08-07T12:57:02+00:00