21443434411 has 4 divisors (see below), whose sum is σ = 24506782192. Its totient is φ = 18380086632.

The previous prime is 21443434393. The next prime is 21443434457. The reversal of 21443434411 is 11443434412.

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 21443434411 - 2⁵ = 21443434379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21443434511) 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, 1531673880 + ... + 1531673893.

It is an arithmetic number, because the mean of its divisors is an integer number (6126695548).

Almost surely, 2^21443434411 is an apocalyptic number.

21443434411 is a deficient number, since it is larger than the sum of its proper divisors (3063347781).

21443434411 is an equidigital number, since it uses as much as digits as its factorization.

21443434411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3063347780.

The product of its digits is 18432, while the sum is 31.

Adding to 21443434411 its reverse (11443434412), we get a palindrome (32886868823).

Subtracting from 21443434411 its reverse (11443434412), we obtain a palindrome (9999999999).

The spelling of 21443434411 in words is "twenty-one billion, four hundred forty-three million, four hundred thirty-four thousand, four hundred eleven".