144

This number is a composite.

144 is the smallest three-digit number in which the sum of the unique digits of the number equals the sum of its unique prime divisors (2 x 2 x 2 x 2 x 3 x 3 = 144 and 1 + 4 = 5 = 2 + 3). [Cramer]

The smallest Fibonacci number divisible by the first two primes. [Gupta]

The smallest square s such that s+1, s-1, s+2 and s-2 are all semiprime. [Bajpai]

If A=1, B=2, C=3, ..., Z=26, then the square root of COUSIN PRIME {-1/+1} are both cousin primes [Homewood]