21042443422043 has 4 divisors (see below), whose sum is σ = 21308803465440. Its totient is φ = 20776083378648.

The previous prime is 21042443422001. The next prime is 21042443422127. The reversal of 21042443422043 is 34022434424012.

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 21042443422043 - 2⁴⁰ = 19942931794267 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21042443421994 and 21042443422012.

It is not an unprimeable number, because it can be changed into a prime (21042443422243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133180021580 + ... + 133180021737.

It is an arithmetic number, because the mean of its divisors is an integer number (5327200866360).

Almost surely, 2^{21042443422043} is an apocalyptic number.

21042443422043 is a deficient number, since it is larger than the sum of its proper divisors (266360043397).

21042443422043 is an equidigital number, since it uses as much as digits as its factorization.

21042443422043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266360043396.

The product of its (nonzero) digits is 147456, while the sum is 35.

Adding to 21042443422043 its reverse (34022434424012), we get a palindrome (55064877846055).

The spelling of 21042443422043 in words is "twenty-one trillion, forty-two billion, four hundred forty-three million, four hundred twenty-two thousand, forty-three".