is 2 2157007 - 1
has 649324 decimal digits
takes 0.142 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LF03D9411882E792Fdouble-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26713.775567.1642%500000150000000.12305.1698%13.898568.8617%1.6975%
PrimeNet2580.017862.0690%100001700000.00182.8095%0.019663.1346%1.0657%
GPU722620.284864.5161%100001600000.00171.5188%0.286665.0551%0.5389%
Difference+5+13.4907+2.6481%+490000+14840000+0.1213+3.6510%+13.6120+3.8067%+3.8067%

Known prime factors (1 factor, 67.8 bits, 0.00314339% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
21570072574868977590525254572167.80359686152562104
23 × 3 × 17 × 73 × 2003966981
2013-04-2773200396698115.82710.40919.441

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-03-07T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.279%
2010-11-04T10:39:00Jocelyn LaroucheManual testing1500015000---0.001--0.237%
2010-11-07T01:16:00Jocelyn LaroucheManual testing3000030000---0.003--0.417%
2010-11-07T12:40:00Jocelyn LaroucheManual testing4500045000---0.004--0.558%
2010-11-10T11:27:00Jocelyn LaroucheManual testing6000060000---0.006--0.675%
2011-01-24T00:12:00markrtiny1200002340000---0.023--2.859%
2016-03-29T11:23:21alpertronManual testing5000001500000012---0.123--5.170%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-01-29T00:00:00ANONYMOUSv4_computers21258--0.018--
2022-03-09T10:13:25LordJuliusManual testing21260--0.071--
2009-01-04T18:33:00Sturle Sundejodel.ifi260261--0.071--
2009-01-07T00:52:00Sturle Sundemorovan.ifi261262--0.142--


ECM factoring results:

Old Calculation Method

Total ECM effort:2.162 GHz-days
Estimated T-Level:1.150
DigitsB1CurvesCompleteFacMiss
201100023 / 1000.23079.361%
255000023 / 2800.08292.100%

New Calculation Method

Total ECM effort:2.162 GHz-days
Estimated T-Level:1.150
DigitsB1CompleteFacMiss
20110000.92939.476%
25500000.08791.713%
302500000.00599.453%


ECM Summary

B1B2factorcurvesGHz-days
10.00000e+0
50000500000090.768
50000690000070.691
50000715000070.703


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-02-07T00:00:00ANONYMOUSv4_computersF03D9411882E792F0.142


PRP results:
dateuseridcompidcofactorsres64PRP
2017-10-08T23:20:30Oliver KruseGTX-2
257486897759052525457
2A65E460336E1A__no
2017-11-18T23:49:35kkmrkkblmbrbkold
257486897759052525457
2A65E460336E1A__no


P-1 factor-bounds graph:
B1 = 500000, B2 = 15000000 (P-1 stage 2)
B1 = 500000 (P-1 stage 1)
B1 = 120000, B2 = 2340000 (P-1 stage 2)
B1 = 120000 (P-1 stage 1)
B1 = 60000 (P-1 stage 1)
B1 = 45000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
100
101
102
103
104
105
106
100
101
102
103
104
105
106
107
108
109
1010
TF factor-bounds graph:
267
262
261
260
258
250
260
270
280
290
2100
Last modified: 2022-08-01T23:02:08+00:00