is 2 8423887 - 1
has 2535843 decimal digits
takes 2.200 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LB695039ECC6D8629double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual2673.527364.1791%5200005200000.19692.5369%3.724265.0878%0.9087%
PrimeNet2640.422562.5000%340009000000.03073.1759%0.453363.6909%1.1909%
GPU722687.075764.7059%5000011000000.04062.1891%7.116365.4785%0.7726%
Difference-1-3.5484-0.5268%+470000-580000+0.1563+0.3478%-3.3921-0.3907%+0.1361%

Known prime factors (1 factor, 69.9 bits, 0.00082960% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
842388710900244534162441414632269.88564698425644613
8501 × 86083 × 88411
2011-01-29860838841125.0260.03260.0663

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2002-09-29T00:00:00ANONYMOUSv4_computers3500035000---0.013--0.623%
2011-01-29T07:13:00Carsten Kossendeymother5200005200002269.8850.1974.3990.3942.537%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1998-11-28T00:00:00ANONYMOUSv4_computers21261--0.036--
1998-12-06T00:00:00ANONYMOUSv4_computers21263--0.189--
1999-09-22T00:00:00ANONYMOUSv4_computers21264--0.423--
1999-12-08T00:00:00ANONYMOUSv4_computers21264--0.423--
2000-01-19T00:00:00ANONYMOUSv4_computers21264--0.423--


ECM factoring results:
No ECM results for M8423887


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-11-17T00:00:00ANONYMOUSv4_computersB695039ECC6D86292.200
2003-03-16T00:00:00ANONYMOUSv4_computers0B9FFC99C399E5__2.200
2003-05-04T00:00:00Team Prime Ribv4_computersB695039ECC6D86292.200


PRP results:
dateuseridcompidcofactorsres64PRP
2018-10-29T05:34:59Oliver KruseGTX-5
1090024453416244141463
E19C14F6473531__no
2020-05-25T22:53:00oodairacom2
1090024453416244141463
E19C14F647353110no


P-1 factor-bounds graph:
B1 = 520000 (P-1 stage 1)
B1 = 35000 (P-1 stage 1)
103
104
105
106
103
104
105
106
TF factor-bounds graph:
267
264
263
261
250
260
270
280
290
2100
Last modified: 2020-05-25T22:53:00+00:00