77777...77777 (49-digits)
This number is a prime.
777777779 9999779666 9779686977 9666977999 9977777777
Just showing those entries submitted by 'Hartley': (Click here to show all)
1111111122222112000211202021120002112222211111111 + 3333333300000330666033065603306660330000033333333 + 3333333377777337000733701073370007337777733333333 = 7777777799999779666977968697796669779999977777777 .
All four numbers are square-congruent primes. [Hartley]
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