is 2 2101873 - 1
has 632727 decimal digits
takes 0.138 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LE42C81F20BEA5E73double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26714.136967.1642%25000001250000000.87468.5666%15.011569.9771%2.8129%
PrimeNet2580.018362.0690%90001600000.00162.6782%0.019963.0848%1.0159%
GPU722620.292364.5161%100001400000.00161.4516%0.293965.0312%0.5151%
Difference+5+13.8446+2.6481%+2490000+124860000+0.8730+7.1151%+14.7176+4.9459%+2.2979%

Known prime factors (1 factor, 76.1 bits, 0.00361929% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2101873794681777286516113563612376.07318904134010154660
22 × 5 × 8443 × 111951522031
2017-11-07844311195152203113,648581.501,086.1

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-05-05T00:00:00Jocelyn Larouchev4_computers10000010000000---0.061--3.706%
2014-08-21T21:47:00Jocelyn LaroucheManual testing130537130537---0.012--1.067%
2014-10-18T13:18:00Jocelyn LaroucheManual testing161074161074---0.015--1.194%
2016-04-27T01:49:09Jocelyn LaroucheManual testing200000742354412---0.057--3.973%
2016-11-08T17:01:22Jocelyn Larouchelow 4M240000240000---0.023--1.461%
2017-06-25T03:43:38mikrMSI250000012500000012---0.875--8.567%
2017-08-19T15:19:12Jocelyn Larouchelow 4M40000040000006---0.057--3.821%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
2002-04-28T00:00:00Jocelyn Larouchev4_computers21259--0.037--
2016-02-23T16:29:05Mark RoseManual testing259260--0.037--
2009-01-03T07:34:00Sturle Sunderodolfo.ifi260261--0.073--
2012-03-26T04:47:00Sebastian HornbostelManual testing261262--0.146--
2013-09-04T10:21:00ramgeisManual testing262263--0.467--
2015-03-15T12:13:00VictordeHollanderManual testing263264--0.934--
2015-03-15T12:13:00VictordeHollanderManual testing264265--1.778--
2015-12-23T09:51:18ramgeisManual testing265266--3.555--
2016-10-01T21:16:25Gordon SpenceManual testing266267--7.111--


ECM factoring results:
Total ECM effort:3.660 GHz-days
Estimated T-Level:20.765
DigitsB1CompleteFacMiss
20110001.65419.131%
25500000.15385.811%
302500000.01099.039%


ECM Summary

B1B2factorcurvesGHz-days
500005000000332.808
500005000000100.851


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-04-23T00:00:00Stephen Woodv4_computersE42C81F20BEA5E730.138


PRP results:
dateuseridcompidcofactorsres64PRP
2017-11-08T00:56:38Oliver KruseGTX-3
79468177728651611356361
4731E805DA8063__no
2017-11-08T19:17:28YarBerManual testing
79468177728651611356361
4731E805DA8063__no


P-1 factor-bounds graph:
B1 = 2500000, B2 = 125000000 (P-1 stage 2)
B1 = 2500000 (P-1 stage 1)
B1 = 100000, B2 = 10000000 (P-1 stage 2)
B1 = 400000, B2 = 4000000 (P-1 stage 2)
B1 = 200000, B2 = 7423544 (P-1 stage 2)
B1 = 400000 (P-1 stage 1)
B1 = 240000 (P-1 stage 1)
B1 = 200000 (P-1 stage 1)
B1 = 161074 (P-1 stage 1)
B1 = 130537 (P-1 stage 1)
B1 = 100000 (P-1 stage 1)
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TF factor-bounds graph:
267
266
265
264
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262
261
260
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2100
Last modified: 2017-11-08T19:17:28+00:00