9940 has 24 divisors (see below), whose sum is σ = 24192.
Its totient is φ = 3360.
The previous prime is 9931. The next prime is 9941. The reversal of 9940 is 499.
It can be divided in two parts, 9 and 940, that added together give a palindrome (949).
9940 = T21 + T22 + ... +
9940 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.
It is a nialpdrome in base 10.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (9941) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 105 + ... + 175.
It is an arithmetic number, because the mean of its divisors is an integer number (1008).
29940 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 9940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12096).
9940 is an abundant number, since it is smaller than the sum of its proper divisors (14252).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
9940 is a wasteful number, since it uses less digits than its factorization.
9940 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 87 (or 85 counting only the distinct ones).
The product of its (nonzero) digits is 324, while the sum is 22.
The square root of 9940 is about 99.6995486449.
The cubic root of 9940 is about 21.5011717407.
The spelling of 9940 in words is "nine thousand, nine hundred forty".