Primality test, prime factorization, all divisors, and GCD/LCM of two integers — the number-theory essentials.
GCD
12
LCM
144
Prime?
No
# Divisors
24
2^3 × 3^2 × 5
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 60, 72, 90, 120, 180, 360