It is a happy number.
18705 is an esthetic number in base 12, because in such base its adjacent digits differ by 1.
It is an alternating number because its digits alternate between odd and even.
18705 is an undulating number in base 12.
It is a plaindrome in base 6.
It is a nialpdrome in base 8.
It is a zygodrome in base 6.
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 18705.
It is a Poulet number, since it divides 218704-1.
218705 is an apocalyptic number.
18705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.
It is an amenable number.
18705 is a wasteful number, since it uses less digits than its factorization.
18705 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 80.
The square root of 18705 is about 136.7662239005. The cubic root of 18705 is about 26.5451940329.
The spelling of 18705 in words is "eighteen thousand, seven hundred five".