21444424443 has 24 divisors (see below), whose sum is σ = 34259567888. Its totient is φ = 12839902272.

The previous prime is 21444424411. The next prime is 21444424481. The reversal of 21444424443 is 34442444412.

It is a happy number.

It is not a de Polignac number, because 21444424443 - 2⁵ = 21444424411 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21444424398 and 21444424407.

It is not an unprimeable number, because it can be changed into a prime (21444424843) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2472505 + ... + 2481162.

Almost surely, 2^21444424443 is an apocalyptic number.

21444424443 is a deficient number, since it is larger than the sum of its proper divisors (12815143445).

21444424443 is a wasteful number, since it uses less digits than its factorization.

21444424443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4953723 (or 4953720 counting only the distinct ones).

The product of its digits is 196608, while the sum is 36.

Adding to 21444424443 its reverse (34442444412), we get a palindrome (55886868855).

The spelling of 21444424443 in words is "twenty-one billion, four hundred forty-four million, four hundred twenty-four thousand, four hundred forty-three".