9865520 has 80 divisors (see below), whose sum is σ = 26664960. Its totient is φ = 3324672.

The previous prime is 9865519. The next prime is 9865523. The reversal of 9865520 is 255689.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (9865523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44129 + ... + 44351.

It is an arithmetic number, because the mean of its divisors is an integer number (333312).

Almost surely, 2^9865520 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 9865520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13332480).

9865520 is an abundant number, since it is smaller than the sum of its proper divisors (16799440).

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

9865520 is a wasteful number, since it uses less digits than its factorization.

9865520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322 (or 316 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 9865520 is about 3140.9425336991. The cubic root of 9865520 is about 214.4733459237.

The spelling of 9865520 in words is "nine million, eight hundred sixty-five thousand, five hundred twenty".