9865856 has 144 divisors (see below), whose sum is σ = 27064170. Its totient is φ = 3548160.

The previous prime is 9865841. The next prime is 9865879. The reversal of 9865856 is 6585689.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 9486400 + 379456 = 3080^2 + 616^2 .

It is a super-2 number, since 2×9865856² = 194670229225472, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 9865856.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 758906 + ... + 758918.

Almost surely, 2^9865856 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 9865856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13532085).

9865856 is an abundant number, since it is smaller than the sum of its proper divisors (17198314).

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

9865856 is a wasteful number, since it uses less digits than its factorization.

9865856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63 (or 33 counting only the distinct ones).

The product of its digits is 518400, while the sum is 47.

The square root of 9865856 is about 3140.9960203732. The cubic root of 9865856 is about 214.4757807413.

The spelling of 9865856 in words is "nine million, eight hundred sixty-five thousand, eight hundred fifty-six".