1985902081

Appears in sequences

• Smallest prime ending a complete Cunningham chain of the second kind (2x-1) of length n.at n=7A110059
• Least number that reaches 1 after n iterations of the map k -> usigma(k)/ud(k) if ud(k) | usigma(k), and k -> 1 otherwise, where ud(k) is the number of unitary divisors of k (A034444) and usigma(k) is their sum (A034448).at n=19A334816