21105453334211 has 4 divisors (see below), whose sum is σ = 21122852719872. Its totient is φ = 21088053948552.

The previous prime is 21105453334181. The next prime is 21105453334253. The reversal of 21105453334211 is 11243335450112.

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 21105453334211 - 2³⁸ = 20830575427267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21105453339211) 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, 8699691011 + ... + 8699693436.

It is an arithmetic number, because the mean of its divisors is an integer number (5280713179968).

Almost surely, 2^{21105453334211} is an apocalyptic number.

21105453334211 is a deficient number, since it is larger than the sum of its proper divisors (17399385661).

21105453334211 is a wasteful number, since it uses less digits than its factorization.

21105453334211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17399385660.

The product of its (nonzero) digits is 43200, while the sum is 35.

Adding to 21105453334211 its reverse (11243335450112), we get a palindrome (32348788784323).

The spelling of 21105453334211 in words is "twenty-one trillion, one hundred five billion, four hundred fifty-three million, three hundred thirty-four thousand, two hundred eleven".