21111222120223 has 4 divisors (see below), whose sum is σ = 21111233999688. Its totient is φ = 21111210240760.

The previous prime is 21111222120193. The next prime is 21111222120257. The reversal of 21111222120223 is 32202122211112.

It is a semiprime because it is the product of two primes, 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 21111222120223 - 2²¹ = 21111220023071 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21111222120194 and 21111222120203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111222120293) 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, 2676433 + ... + 7027498.

It is an arithmetic number, because the mean of its divisors is an integer number (5277808499922).

Almost surely, 2^{21111222120223} is an apocalyptic number.

21111222120223 is a deficient number, since it is larger than the sum of its proper divisors (11879465).

21111222120223 is an equidigital number, since it uses as much as digits as its factorization.

21111222120223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11879464.

The product of its (nonzero) digits is 384, while the sum is 22.

Adding to 21111222120223 its reverse (32202122211112), we get a palindrome (53313344331335).

The spelling of 21111222120223 in words is "twenty-one trillion, one hundred eleven billion, two hundred twenty-two million, one hundred twenty thousand, two hundred twenty-three".