WolframLang nth Prime
WolframLang Prime

Table[ Timing[ {x, Prime[ 10^x ]} ] , {x, 1, 15}]

Timing[ {x, Prime[ 10^x ]} ] /. x -> 18 N[ Prime[ 10^18 ], 19 ] N[ 10^18 +1 , 19 ]

it stops computing at 10^18.

Table[ Timing[ {x, Prime[ 10^x ]} ] , {x, 1, 15}]
Timing[ {x, Prime[ 10^x ]} ] /. x -> 18 N[ Prime[ 10^18 ], 19 ] N[ 10^18 +1 , 19 ]
it stops computing at 10^18.