21432022421 has 4 divisors (see below), whose sum is σ = 21432331200. Its totient is φ = 21431713644.

The previous prime is 21432022397. The next prime is 21432022433. The reversal of 21432022421 is 12422023412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21432022421 - 2³⁰ = 20358280597 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432022471) 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, 3650 + ... + 207068.

It is an arithmetic number, because the mean of its divisors is an integer number (5358082800).

Almost surely, 2^21432022421 is an apocalyptic number.

It is an amenable number.

21432022421 is a deficient number, since it is larger than the sum of its proper divisors (308779).

21432022421 is a wasteful number, since it uses less digits than its factorization.

21432022421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 308778.

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21432022421 its reverse (12422023412), we get a palindrome (33854045833).

Subtracting from 21432022421 its reverse (12422023412), we obtain a palindrome (9009999009).

The spelling of 21432022421 in words is "twenty-one billion, four hundred thirty-two million, twenty-two thousand, four hundred twenty-one".