Perfect totient numbers

use Prime::Factor;

my \πœ‘ = lazy 0, |(1..*).hyper.map: -> \t { t * [*] t.&prime-factors.squish.map: 1 - 1/* }
my \πœ‘πœ‘ = Nil, |(3, *+2 … *).grep: -> \p { p == sum πœ‘[p], { πœ‘[$_] } … 1 };

put "The first twenty Perfect totient numbers:\n",  πœ‘πœ‘[1..20];

Output:

The first twenty Perfect totient numbers:
3 9 15 27 39 81 111 183 243 255 327 363 471 729 2187 2199 3063 4359 4375 5571

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