| History of Cunningham Chain length 19 | |||
| Initial prime number | Digits | When | Discoverer |
|---|---|---|---|
| 1st kind | |||
| 27692774713034525184617669 | 26 | 11 Apr 2026 | John Armitage |
| 2nd kind | |||
| 79910197721667870187016101 | 26 | 23 Mar 2014 | Raanan Chermoni; Jaroslaw Wroblewski |
| 42008163485623434922152331 | 26 | 15 Mar 2014 | Raanan Chermoni; Jaroslaw Wroblewski |
| 6705789932932200509702161 | 25 | 28 Mar 2026 | John Armitage |