Adding to 19740 its reverse (4791), we get a triangular number (24531 = T221).
It is a nialpdrome in base 12.
It is a congruent number.
It is an unprimeable number.
219740 is an apocalyptic number.
19740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 19740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32256).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
19740 is a wasteful number, since it uses less digits than its factorization.
19740 is an odious number, because the sum of its binary digits is odd.
The square root of 19740 is about 140.4991103175. The cubic root of 19740 is about 27.0260379818.
The spelling of 19740 in words is "nineteen thousand, seven hundred forty".