• 219 can be written using four 4's:
It is a happy number.
219 is nontrivially palindromic in base 2 and base 8.
219 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.
It is a semiprime because it is the product of two primes.
It is an Ulam number.
It is a D-number.
It is a Duffinian number.
219 is a lucky number.
219 is a nontrivial repdigit in base 8.
It is a plaindrome in base 5, base 8, base 11, base 13 and base 14.
It is a nialpdrome in base 7, base 8, base 15 and base 16.
It is a zygodrome in base 8.
It is a congruent number.
It is a panconsummate number.
219 is an equidigital number, since it uses as much as digits as its factorization.
219 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 76.
The square root of 219 is about 14.7986485869. The cubic root of 219 is about 6.0276501601.
Adding to 219 its sum of digits (12), we get a triangular number (231 = T21).
Multiplying 219 by its sum of digits (12), we get a triangular number (2628 = T72).
The spelling of 219 in words is "two hundred nineteen", and thus it is an aban number.