| 2621 | Composite, with 3 known prime factors. Cofactor is composite. Trial Factored to 268 TF target 244 |
| Factored | |
| ECM | | Digits | B1 | Curves |
|---|
| 25 | 50000 | 280 / 280 | | 30 | 250000 | 640 / 640 | | 35 | 1000000 | 1566 / 1566 | | 40 | 3000000 | 4588 / 4588 | | 45 | 11000000 | 9201 / 9201 | | 50 | 44000000 | 16550 / 16550 | | 55 | 110000000 | 12104 / 40830 |
Estimated T-Level: 51.5 ⓘ TF below 2^166 is very unlikely to find new factors due to ECM effort. |
| PRP Cofactor | | Status | Proof | Date | User | Residue | Number of known factors | Shift | Type | Base |
|---|
| Verified | No proof (small exponent) | 2017-09-21 | Oliver Kruse | 1BCF7091F6646425 | 3 | 0 | 1 | 3 | | Verified | No proof (small exponent) | 2017-10-12 | kkmrkkblmbrbk | 1BCF7091F6646425 | 3 | 2470 | 1 | 3 | | Verified | No proof (small exponent) | 2020-04-17 | Oliver Kruse | 7186CDBF4EF5E441 | 3 | 970 | 5 | 3 | | Verified | No proof (small exponent) | 2024-02-03 | Wentao Huang | 7186CDBF4EF5E441 | 3 | 2500 | 5 | 3 |
|
| History | | Date | User | Type | Result |
|---|
| 2025-04-12 | masser | NF-PP1 | Start=141/37, B1=4300000000, B2=4295700000000 | | 2024-02-03 | Wentao Huang | C-PRP | M2621/15727/12895321/13489674267041509343311 : 7186CDBF4EF5E441 | | 2022-02-08 | mikr | NF-PM1 | B1=60000000000, B2=314766415184771550 | | 2021-07-05 | ViliamF | NF-PM1 | B1=1000000000, B2=191000000000 | | 2020-04-17 | Oliver Kruse | C-PRP | M2621/15727/12895321/13489674267041509343311 : 7186CDBF4EF5E441 | | 2017-10-12 | kkmrkkblmbrbk | C-PRP | M2621/15727/12895321/13489674267041509343311 : 1BCF7091F6646425 | | 2017-09-21 | Oliver Kruse | C-PRP | M2621/15727/12895321/13489674267041509343311 : 1BCF7091F6646425 | | 2017-09-21 | Oliver Kruse | C-PRP | M2621/15727/12895321/13489674267041509343311 : 1BCF7091F6646425 |
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