9889840 has 40 divisors (see below), whose sum is σ = 23154768. Its totient is φ = 3928320.

The previous prime is 9889813. The next prime is 9889843. The reversal of 9889840 is 489889.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (9889843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14139 + ... + 14821.

Almost surely, 2^9889840 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 9889840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11577384).

9889840 is an abundant number, since it is smaller than the sum of its proper divisors (13264928).

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

9889840 is a wasteful number, since it uses less digits than its factorization.

9889840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 877 (or 871 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 46.

The square root of 9889840 is about 3144.8116000804. The cubic root of 9889840 is about 214.6494377250.

The spelling of 9889840 in words is "nine million, eight hundred eighty-nine thousand, eight hundred forty".