12021856 has 144 divisors (see below), whose sum is σ = 32577552. Its totient is φ = 4300800.

The previous prime is 12021817. The next prime is 12021857. The reversal of 12021856 is 65812021.

It is a self number, because there is not a number n which added to its sum of digits gives 12021856.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12021857) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 293196 + ... + 293236.

It is an arithmetic number, because the mean of its divisors is an integer number (226233).

Almost surely, 2^12021856 is an apocalyptic number.

12021856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12021856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16288776).

12021856 is an abundant number, since it is smaller than the sum of its proper divisors (20555696).

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

12021856 is a wasteful number, since it uses less digits than its factorization.

12021856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 12021856 is about 3467.2548219016. The cubic root of 12021856 is about 229.0817579584.

Adding to 12021856 its reverse (65812021), we get a palindrome (77833877).

The spelling of 12021856 in words is "twelve million, twenty-one thousand, eight hundred fifty-six".