21111103211 has 4 divisors (see below), whose sum is σ = 23030294424. Its totient is φ = 19191912000.

The previous prime is 21111103177. The next prime is 21111103241. The reversal of 21111103211 is 11230111112.

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 21111103211 - 2⁶ = 21111103147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21111103241) 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, 959595590 + ... + 959595611.

It is an arithmetic number, because the mean of its divisors is an integer number (5757573606).

Almost surely, 2^21111103211 is an apocalyptic number.

21111103211 is a deficient number, since it is larger than the sum of its proper divisors (1919191213).

21111103211 is a wasteful number, since it uses less digits than its factorization.

21111103211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1919191212.

The product of its (nonzero) digits is 12, while the sum is 14.

Adding to 21111103211 its reverse (11230111112), we get a palindrome (32341214323).

The spelling of 21111103211 in words is "twenty-one billion, one hundred eleven million, one hundred three thousand, two hundred eleven".