21204214441 has 4 divisors (see below), whose sum is σ = 22126136832. Its totient is φ = 20282292052.

The previous prime is 21204214433. The next prime is 21204214457. The reversal of 21204214441 is 14441240212.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 21204214441 - 2³ = 21204214433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21204212441) 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, 460961161 + ... + 460961206.

It is an arithmetic number, because the mean of its divisors is an integer number (5531534208).

Almost surely, 2^21204214441 is an apocalyptic number.

It is an amenable number.

21204214441 is a deficient number, since it is larger than the sum of its proper divisors (921922391).

21204214441 is an equidigital number, since it uses as much as digits as its factorization.

21204214441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 921922390.

The product of its (nonzero) digits is 2048, while the sum is 25.

Adding to 21204214441 its reverse (14441240212), we get a palindrome (35645454653).

The spelling of 21204214441 in words is "twenty-one billion, two hundred four million, two hundred fourteen thousand, four hundred forty-one".