99209

Appears in sequences

• a(n) = (10n+1)*(10n+9).at n=31A001535
• Quasi-Carmichael numbers to base -7: squarefree composites n such that prime p|n ==> p+7|n+7.at n=17A029567
• Sum of first n palindromic primes A002385.at n=27A046485