is 2 258421 - 1
has 77793 decimal digits
takes 0.002 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L6271683FFC4B1D2Ddouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual267114.982673.1343%30000000100358126969105,417.947323.4493%5,532.929979.4341%6.2998%
PrimeNet2400.000055.0000%2600700000.000114.2727%0.000161.4227%6.4227%
GPU722440.000059.0909%45001200000.000110.3918%0.000163.3421%4.2512%
Difference+23+114.9826+14.0434%+29995500+10035812576910+5,417.9472+13.0575%+5,532.9298+16.0920%+16.0920%

Known prime factors (3 factors, 265.8 bits, 0.10286185% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2584211522405110810406012156408572786.976294559093651523291868
22 × 3 × 269 × 9229751 × 9886644631
2020-09-3092297519886644631107,740,0905.42369.968
2584214110002506940204481557014392788.409795214496294845326339
3 × 265071498764948442113
2009-04-203265071498764948442113304,476,0161.431e+112.673e+11
25842116688119747562992775372048392890.4313228862930559628044039
7 × 37 × 743 × 16778805170313547
2017-06-02743167788051703135471.789e+99,057,75816,917,370

4 Composite Factors:
exponentprime factorscomposite factordigitsbits*
25842162570888220093485087695525148496129408944366742093
223
53175.386
25842125406078793505962823130625259682435136927193986650
7023
54177.407
25842168588213998602232675057851443864446085775104147006
3321
54178.840
25842110441904753282987286945463601062519333772721769675
3916558175275717142915384706097
81265.817
P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2000-12-31T00:00:00ANONYMOUSv4_computers950003800000---0.003--2.203%
2001-06-17T00:00:00ANONYMOUSv4_computers10000010000000---0.006--2.725%
2002-06-02T00:00:00ANONYMOUSv4_computers327683276800---0.002--1.562%
2002-08-10T00:00:00ANONYMOUSv4_computers655366553600---0.004--2.245%
2003-03-07T00:00:00ANONYMOUSv4_computers13107213107200---0.008--3.057%
2003-11-08T00:00:00ANONYMOUSv4_computers26214426214400---0.017--3.984%
2021-08-25T14:39:23Oliver KruseOllaptop30000000300000000024---1.901--12.599%
2022-04-30T06:31:25Oliver KruseThreadripper-PC3000000010035812696910-
skipped known factor: 152240511081040601215640857
--5,418--23.449%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-11-24T00:00:00ANONYMOUSv4_computers252253--0.002--
2000-04-27T00:00:00ANONYMOUSv4_computers21254--0.009--
2000-12-31T00:00:00ANONYMOUSv4_computers21255--0.019--
2001-02-18T00:00:00ANONYMOUSv4_computers21256--0.037--
2002-03-24T00:00:00ANONYMOUSv4_computers21257--0.074--
2022-03-07T05:52:30LordJuliusManual testing257258--0.074--
2009-01-01T21:04:00Sturle Sundegorro.ifi258259--0.149--
2009-01-25T12:25:00Sturle Sundegooch.ifi259260--0.297--


ECM factoring results:

Old Calculation Method

Total ECM effort:10.407 GHz-days
Estimated T-Level:26.906
DigitsB1CurvesCompleteFacMiss
2011000433 / 1004.3301.288%
2550000433 / 2801.54621.242%
30250000244 / 6400.38168.280%

New Calculation Method

Total ECM effort:10.407 GHz-days
Estimated T-Level:26.906
DigitsB1CompleteFacMiss
201100026.4300.000%
25500003.5142.978%
302500000.35470.193%
3510000000.02897.220%
4030000000.00299.816%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
5000050000001891.378
250000250000002107.653
2500002500000020.073
25000025000000110.401
25000038500000210.903


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
2001-10-13T00:00:00ANONYMOUSv4_computers6271683FFC4B1D2D0.002


PRP results:
dateuseridcompidcofactorsres64PRP
2017-09-22T08:12:58Oliver KruseDoppelherz
411000250694020448155701439
1668811974756299277537204839
F8E414EBDF34F403no
2017-09-22T10:03:09Oliver KruseManual testing
411000250694020448155701439
1668811974756299277537204839
F8E414EBDF34F403no
2017-10-12T17:19:13Oliver KruseGTX-0F8E414EBDF34F4__no
2017-11-06T16:57:15kkmrkkblmbrbkc4.xlarge
411000250694020448155701439
1668811974756299277537204839
F8E414EBDF34F4__no
2020-04-17T20:16:24Oliver KruseAddPrpType5
411000250694020448155701439
1668811974756299277537204839
9ADDDA3750641A__no
2020-10-01T15:22:36mnd9vv
152240511081040601215640857
411000250694020448155701439
1668811974756299277537204839
9ADDDA3750641A63no
2020-10-03T00:40:08fre_gamesgpu
152240511081040601215640857
411000250694020448155701439
1668811974756299277537204839
9ADDDA3750641A63no


P-1 factor-bounds graph:
B1 = 30000000, B2 = 10035812696910 (P-1 stage 2)
B1 = 30000000, B2 = 3000000000 (P-1 stage 2)
B1 = 30000000 (P-1 stage 1)
B1 = 262144, B2 = 26214400 (P-1 stage 2)
B1 = 131072, B2 = 13107200 (P-1 stage 2)
B1 = 100000, B2 = 10000000 (P-1 stage 2)
B1 = 65536, B2 = 6553600 (P-1 stage 2)
B1 = 95000, B2 = 3800000 (P-1 stage 2)
B1 = 262144 (P-1 stage 1)
B1 = 32768, B2 = 3276800 (P-1 stage 2)
B1 = 131072 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
B1 = 95000 (P-1 stage 1)
B1 = 65536 (P-1 stage 1)
B1 = 32768 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2022-05-15T16:11:30+00:00