I have a list, e.g, {2, 9, 2, 9, 1, 10, 1, 1, 3, 1, 8, 2, 8, 2}
(representing a solution of a numbers puzzle but not important) and I
need to make it the number 292911011318282
one way
lst = {2, 9, 2, 9, 1, 10, 1, 1, 3, 1, 8, 2, 8, 2};
FromDigits[lst]
(* 29292011318282 *)
another way
lst = {2, 9, 2, 9, 1, 10, 1, 1, 3, 1, 8, 2, 8, 2};
ToExpression@StringJoin[ToString[#] & /@ lst]
(*292911011318282*)