is 2 2827621 - 1
has 851199 decimal digits
takes 0.218 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-L-unknown--unknown-
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbability
Actual26710.508567.1642 %3600002873801701.79168.0003 %12.300169.7911 %
Target2630.564465.0794 %1600013000000.00961.8262 %0.574165.7171 %
Difference+4+9.9440+2.0848 %+344000+286080170+1.7820+6.1741%+11.7260+4.0740 %

Known prime factors (1 factor, 46.2 bits, 0.00163556% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2827621835321092190811446.24714770740
22 × 3 × 5 × 173 × 1423
-17314233.746e-62.700e-53.943e-5

P-1 results:
dateusercompB1B2BSstagefactordigitsbits*GHz-daysFac Prob
2023-01-28Lisander ViaeneDesktop72000281496600
skipped known factor: 83532109219081
--2.0128.982%
2023-01-30USAFSS6917th_Scty_Sq360000287380170
skipped known factor: 83532109219081
--1.97411.285%


Trial Factoring results:
5758596061626364656667
No TF results for M2827621


ECM factoring results:
Total ECM effort:0.313 GHz-days
Estimated T-Level:0.577
DigitsB1CompleteFacMiss
20110000.11589.102%
25500000.01198.938%


ECM Summary

B1B2factorcurvesGHz-days
50000500000030.313


Lucas-Lehmer results:
No L-L results for M2827621


PRP results:
dateuseridcompidcofactorsres64
2017-10-22Oliver KruseGTX-3
83532109219081
089938FE3941F538
2017-12-07kkmrkkblmbrbkc4.xlarge
83532109219081
089938FE3941F538


CERT results:
No CERT results for M2827621


P-1 factor-bounds graph:
B1 = 360000, B2 = 287380170 (P-1 stage 2)
B1 = 72000, B2 = 281496600 (P-1 stage 2)
B1 = 360000 (P-1 stage 1)
B1 = 72000 (P-1 stage 1)
101
102
103
104
105
106
101
102
103
104
105
106
107
108
109
TF factor-bounds graph:
this exponent TF target: 63
TF double-checked to: 67
ECM T-Level=0.58 ~= -15-bit
250
260
270
JSON version of this page
Last modified: 2024-03-13T02:15:48+00:00