It is a happy number.
It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 73481 = 197 ⋅373.
It is a cyclic number.
It is a Duffinian number.
It is a congruent number.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 18437.
218437 is an apocalyptic number.
It is an amenable number.
18437 is a wasteful number, since it uses less digits than its factorization.
18437 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 282.
The square root of 18437 is about 135.7829149783. The cubic root of 18437 is about 26.4178063221.
The spelling of 18437 in words is "eighteen thousand, four hundred thirty-seven".