is 2 2478937 - 1
has 746235 decimal digits
takes 0.172 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L402326B232982DF9double-checked
PRP3767614C76C60404verified PRP

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26824.044567.6471%2382500857701000.69657.5475%24.741170.0889%2.4418%
PrimeNet2590.031062.7119%100001800000.00192.5339%0.032963.6567%0.9448%
GPU722630.643865.0794%110001600000.00191.3797%0.645865.5612%0.4818%
Difference+5+23.4007+2.5677%+2371500+85610100+0.6946+6.1678%+24.0953+4.5277%+4.5277%

Known prime factors (1 factor, 77.2 bits, 0.00311554% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
24789371775081752183459985392072477.23235803284879435419
23 × 13597 × 114485883649
2020-12-131359711448588364919,240627.331,171.7

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-14T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.234%
2003-10-31T00:00:00Team Prime Ribv4_computers15000228750---0.003--0.785%
2010-11-20T12:24:00Jocelyn LaroucheManual testing2000020000---0.002--0.263%
2011-01-20T11:04:00Oscar Östlin950001947500---0.020--2.378%
2014-09-02T00:10:00Jocelyn LaroucheManual testing120892120892---0.012--0.917%
2014-10-27T05:20:00mikrMSI238250085770100---0.697--7.547%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-05-02T00:00:00ANONYMOUSv4_computers21259--0.031--
2016-02-23T16:29:15Mark RoseManual testing259260--0.031--
2009-01-15T06:26:00Sturle Sundehindemith.ifi260261--0.062--
2012-06-09T00:43:00Sebastian HornbostelManual testing261262--0.124--
2013-08-21T03:34:00David CampeauManual testing262263--0.396--
2015-03-03T21:37:00VictordeHollanderManual testing263264--0.792--
2015-03-03T21:37:00VictordeHollanderManual testing264265--1.507--
2015-10-29T11:36:21ramgeisManual testing265266--3.014--
2017-07-22T20:28:36Gordon SpenceManual testing266267--6.029--
2019-05-27T13:36:57TJAOIManual testing267268--12.06--


ECM factoring results:

Old Calculation Method

Total ECM effort:8.356 GHz-days
Estimated T-Level:4.550
DigitsB1CurvesCompleteFacMiss
201100091 / 1000.91040.068%
255000091 / 2800.32572.211%

New Calculation Method

Total ECM effort:8.356 GHz-days
Estimated T-Level:4.550
DigitsB1CompleteFacMiss
20110003.5003.020%
25500000.32472.336%
302500000.02097.978%


ECM Summary

B1B2factorcurvesGHz-days
500005000000908.264
50000500000010.092


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-08-16T00:00:00ANONYMOUSv4_computers402326B232982DF90.172
1999-09-30T00:00:00ANONYMOUSv4_computers402326B232982DF90.172
2018-05-30T03:45:20kkmrkkblmbrbkold402326B232982DF90.172


PRP results:
dateuseridcompidcofactorsres64PRP
2020-12-14T06:42:38JayderBlack_Adder
177508175218345998539207
3767614C76C60404no


P-1 factor-bounds graph:
B1 = 2382500, B2 = 85770100 (P-1 stage 2)
B1 = 2382500 (P-1 stage 1)
B1 = 95000, B2 = 1947500 (P-1 stage 2)
B1 = 120892 (P-1 stage 1)
B1 = 95000 (P-1 stage 1)
B1 = 15000, B2 = 228750 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
102
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107
102
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104
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109
1010
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1012
TF factor-bounds graph:
268
267
266
265
264
263
262
261
260
259
250
260
270
280
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2100
Last modified: 2020-12-14T06:42:38+00:00