2011856 has 80 divisors (see below), whose sum is σ = 5142528. Its totient is φ = 739200.

The previous prime is 2011843. The next prime is 2011861. The reversal of 2011856 is 6581102.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28301 + ... + 28371.

2^2011856 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 2011856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2571264).

2011856 is an abundant number, since it is smaller than the sum of its proper divisors (3130672).

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

2011856 is a wasteful number, since it uses less digits than its factorization.

2011856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120 (or 114 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 2011856 is about 1418.3990975744. The cubic root of 2011856 is about 126.2405750570.

Adding to 2011856 its reverse (6581102), we get a palindrome (8592958).

The spelling of 2011856 in words is "two million, eleven thousand, eight hundred fifty-six".