2181824 has 28 divisors (see below), whose sum is σ = 4398264. Its totient is φ = 1073664.

The previous prime is 2181737. The next prime is 2181833. The reversal of 2181824 is 4281812.

It is a nude number because it is divisible by every one of its digits.

It is a zygodrome in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 2181793 and 2181802.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4439 + ... + 4905.

2^2181824 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 2181824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2199132).

2181824 is an abundant number, since it is smaller than the sum of its proper divisors (2216440).

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

2181824 is an equidigital number, since it uses as much as digits as its factorization.

2181824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 552 (or 542 counting only the distinct ones).

The product of its digits is 1024, while the sum is 26.

The square root of 2181824 is about 1477.0998612145. The cubic root of 2181824 is about 129.6999787383.

The spelling of 2181824 in words is "two million, one hundred eighty-one thousand, eight hundred twenty-four".