Superperfect Number: Perfect Number, Mersenne Prme, Divisor Function, 2 (Number), 4 (Number)

Weird Number: Natural Number, Number Theory, Divisor

Semiperfect Number: Mathematics, Number Theory, Natural Number, Proper Divisor, Perfect Prime

Untouchable Number: Integer, Sum, Proper Divisor, Goldbach Conjecture, Composite Number, Perfect Number

Prime Number: Natural Number, Divisor, Number Theorem, Primality Test, Largest Known Mersenne...