9 · 21807574 + 1
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At this site we maintain a list of the 5000 Largest Known Primes which is updated hourly. This list is the most important databases at The Prime Pages: a collection of research, records and results all about prime numbers. This page summarizes our information about one of these primes.

This prime's information:

field (help)value
Description:9 · 21807574 + 1
Verification status (*):Proven
Official Comment:Generalized Fermat
Unofficial Comments:This prime has 1 user comment below.
Proof-code(s): (*):L2419 : Gathright, PSieve, Srsieve, PrimeGrid, LLR
Decimal Digits:544135   (log10 is 544134.94762483)
Rank (*):1712 (digit rank is 1)
Entrance Rank (*):111
Currently on list? (*):yes
Submitted:6/22/2011 05:01:39 CDT
Last modified:6/22/2011 07:20:20 CDT
Database id:100561
Status Flags:none
Score (*):44.7649 (normalized score 2.4564)

Archival tags:

There are certain forms classed as archivable: these prime may (at times) remain on this list even if they do not make the Top 5000 proper.  Such primes are tracked with archival tags.
Generalized Fermat (archivable *)
Prime on list: no, rank 166
Subcategory: "Generalized Fermat"
(archival tag id 213315, tag last modified 2018-07-06 11:50:19)

User comments about this prime (disclaimer):

User comments are allowed to convey mathematical information about this number, how it was proven prime.... See our guidelines and restrictions.

PrimeGrid writes (11 Sep 2014): 
9*2^1807574+1 Divides xGF(1807570,4,3)
9*2^1807574+1 Divides xGF(1807572,7,6)
9*2^1807574+1 Divides xGF(1807572,8,7)

Verification data:

The Top 5000 Primes is a list for proven primes only. In order to maintain the integrity of this list, we seek to verify the primality of all submissions.  We are currently unable to check all proofs (ECPP, KP, ...), but we will at least trial divide and PRP check every entry before it is included in the list.
machineDitto P4 P4
notesCommand: /home/ditto/client/TrialDiv/TrialDiv -q 9 2 1807574 1 2>&1
[Elapsed time: 10.563 seconds]
modified2011-12-27 16:48:32
created2011-06-22 05:05:02

machineDitto P4 P4
notesCommand: /home/ditto/client/pfgw -t -q"9*2^1807574+1" 2>&1
PFGW Version [GWNUM 26.5]
Primality testing 9*2^1807574+1 [N-1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 5
Calling Brillhart-Lehmer-Selfridge with factored part 100.00%
9*2^1807574+1 is prime! (7676.2853s+0.0014s)
[Elapsed time: 2.13 hours]
modified2011-12-27 16:48:32
created2011-06-22 05:08:02

Query times: 0.0004 seconds to select prime, 0.0009 seconds to seek comments.