21410443013221 has 4 divisors (see below), whose sum is σ = 21410454679744. Its totient is φ = 21410431346700.

The previous prime is 21410443013177. The next prime is 21410443013233. The reversal of 21410443013221 is 12231034401412.

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, 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 21410443013221 - 2²¹ = 21410440916069 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21410443013221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21410443013261) 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, 2411325 + ... + 6973906.

It is an arithmetic number, because the mean of its divisors is an integer number (5352613669936).

Almost surely, 2^{21410443013221} is an apocalyptic number.

It is an amenable number.

21410443013221 is a deficient number, since it is larger than the sum of its proper divisors (11666523).

21410443013221 is an equidigital number, since it uses as much as digits as its factorization.

21410443013221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11666522.

The product of its (nonzero) digits is 4608, while the sum is 28.

Adding to 21410443013221 its reverse (12231034401412), we get a palindrome (33641477414633).

The spelling of 21410443013221 in words is "twenty-one trillion, four hundred ten billion, four hundred forty-three million, thirteen thousand, two hundred twenty-one".