57927

Appears in sequences

• a(1) = 1; then the smallest number such that both the forward and reverse n-th partial concatenation is a prime for n > 1. (Reverse concatenation is taken term-wise and not digit-wise.)at n=39A083992
• In binary representation: least number, k, which occurs n times in its factorial.at n=28A093826
• Numbers k such that k and k^2 use only the digits 2, 3, 5, 7 and 9.at n=18A137084
• Numbers k such that there is no prime p and index j < k such that A002182(k) = p * A002182(j).at n=21A272606