It is a nialpdrome in base 9.
It is a zygodrome in base 9.
It is a congruent number.
It is an unprimeable number.
243740 is an apocalyptic number.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 43740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68880).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
43740 is an equidigital number, since it uses as much as digits as its factorization.
43740 is an odious number, because the sum of its binary digits is odd.
The square root of 43740 is about 209.1411006952. The cubic root of 43740 is about 35.2338087705.
The spelling of 43740 in words is "forty-three thousand, seven hundred forty", and thus it is an iban number.