21211102111 has 4 divisors (see below), whose sum is σ = 21220338672. Its totient is φ = 21201865552.

The previous prime is 21211102091. The next prime is 21211102127. The reversal of 21211102111 is 11120111212.

It is a happy number.

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 21211102111 - 2⁹ = 21211101599 is a prime.

It is a super-3 number, since 3×21211102111³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21211102091 and 21211102100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211102141) 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, 4614835 + ... + 4619428.

It is an arithmetic number, because the mean of its divisors is an integer number (5305084668).

Almost surely, 2^21211102111 is an apocalyptic number.

21211102111 is a deficient number, since it is larger than the sum of its proper divisors (9236561).

21211102111 is an equidigital number, since it uses as much as digits as its factorization.

21211102111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9236560.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21211102111 its reverse (11120111212), we get a palindrome (32331213323).

The spelling of 21211102111 in words is "twenty-one billion, two hundred eleven million, one hundred two thousand, one hundred eleven".