4423443121 has 4 divisors (see below), whose sum is σ = 4495958644. Its totient is φ = 4350927600.

The previous prime is 4423443097. The next prime is 4423443127. The reversal of 4423443121 is 1213443244.

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

It can be written as a sum of positive squares in 2 ways, for example, as 235929600 + 4187513521 = 15360^2 + 64711^2 .

It is a cyclic number.

It is not a de Polignac number, because 4423443121 - 2¹¹ = 4423441073 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 4423443121.

It is not an unprimeable number, because it can be changed into a prime (4423443127) 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, 36257670 + ... + 36257791.

It is an arithmetic number, because the mean of its divisors is an integer number (1123989661).

Almost surely, 2^4423443121 is an apocalyptic number.

It is an amenable number.

4423443121 is a deficient number, since it is larger than the sum of its proper divisors (72515523).

4423443121 is an equidigital number, since it uses as much as digits as its factorization.

4423443121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72515522.

The product of its digits is 9216, while the sum is 28.

The square root of 4423443121 is about 66508.9702295863. The cubic root of 4423443121 is about 1641.5476072600.

Adding to 4423443121 its reverse (1213443244), we get a palindrome (5636886365).

The spelling of 4423443121 in words is "four billion, four hundred twenty-three million, four hundred forty-three thousand, one hundred twenty-one".