9870 has 32 divisors (see below), whose sum is σ = 27648. Its totient is φ = 2208.

The previous prime is 9859. The next prime is 9871. The reversal of 9870 is 789.

9870 = T₄ + T₅ + ... + T₃₈.

9870 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

9870 is a nontrivial binomial coefficient, being equal to C(141, 2).

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is a plaindrome in base 16.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 9870.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9871) 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 15 ways as a sum of consecutive naturals, for example, 187 + ... + 233.

It is an arithmetic number, because the mean of its divisors is an integer number (864).

2⁹⁸⁷⁰ is an apocalyptic number.

9870 is the 140-th triangular number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9870, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13824).

9870 is an abundant number, since it is smaller than the sum of its proper divisors (17778).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9870 is a wasteful number, since it uses less digits than its factorization.

9870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64.

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 9870 is about 99.3478736562. The cubic root of 9870 is about 21.4505805614.

The spelling of 9870 in words is "nine thousand, eight hundred seventy".