as an alternative to %f you could format integers as strings with %s.

  DB<137> $val=1214395
 => 1214395

  DB<138> sprintf("%011s", $val);
 => "00001214395"

  DB<139> $val="12143951645"
 => "12143951645"

  DB<140> sprintf("%011s", $val);
 => "12143951645"
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So no overflow possible, but don't expect numeric conversions of floats then.

There is some documentation about manipulating the size of integers, but I couldn't understand how.¹

update

¹) tl;dr ;-)

between % and $, but still platform specific

  DB<161> $val="12143951645"
 => "12143951645"

  DB<162> sprintf("%ll$11d", $val);
 => -1
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