21211120121223 has 4 divisors (see below), whose sum is σ = 28281493494968. Its totient is φ = 14140746747480.

The previous prime is 21211120121207. The next prime is 21211120121273. The reversal of 21211120121223 is 32212102111212.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21211120121223 - 2⁴ = 21211120121207 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 21211120121223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211120121203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3535186686868 + ... + 3535186686873.

It is an arithmetic number, because the mean of its divisors is an integer number (7070373373742).

Almost surely, 2^{21211120121223} is an apocalyptic number.

21211120121223 is a deficient number, since it is larger than the sum of its proper divisors (7070373373745).

21211120121223 is an equidigital number, since it uses as much as digits as its factorization.

21211120121223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7070373373744.

The product of its (nonzero) digits is 192, while the sum is 21.

Adding to 21211120121223 its reverse (32212102111212), we get a palindrome (53423222232435).

The spelling of 21211120121223 in words is "twenty-one trillion, two hundred eleven billion, one hundred twenty million, one hundred twenty-one thousand, two hundred twenty-three".