2181443 has 4 divisors (see below), whose sum is σ = 2379768. Its totient is φ = 1983120.

The previous prime is 2181419. The next prime is 2181449. The reversal of 2181443 is 3441812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2181443 - 2⁶ = 2181379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2181449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99146 + ... + 99167.

It is an arithmetic number, because the mean of its divisors is an integer number (594942).

2^2181443 is an apocalyptic number.

2181443 is a deficient number, since it is larger than the sum of its proper divisors (198325).

2181443 is a wasteful number, since it uses less digits than its factorization.

2181443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198324.

The product of its digits is 768, while the sum is 23.

The square root of 2181443 is about 1476.9708866460. The cubic root of 2181443 is about 129.6924286993.

It can be divided in two parts, 218 and 1443, that added together give a palindrome (1661).

The spelling of 2181443 in words is "two million, one hundred eighty-one thousand, four hundred forty-three".