Adding to 9720 its reverse (279), we get a palindrome (9999).
9720 is nontrivially palindromic in base 11.
It is a plaindrome in base 13.
It is a nialpdrome in base 3 and base 10.
It is a zygodrome in base 3.
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 9720.
29720 is an apocalyptic number.
9720 is a gapful number since it is divisible by the number (90) 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 9720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16380).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
9720 is a wasteful number, since it uses less digits than its factorization.
9720 is an evil number, because the sum of its binary digits is even.
The square root of 9720 is about 98.5900603509. The cubic root of 9720 is about 21.3413598269.
The spelling of 9720 in words is "nine thousand, seven hundred twenty".