21102112211 has 4 divisors (see below), whose sum is σ = 21129842424. Its totient is φ = 21074382000.

The previous prime is 21102112201. The next prime is 21102112219. The reversal of 21102112211 is 11221120112.

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 21102112211 - 2⁶ = 21102112147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21102112219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13863965 + ... + 13865486.

It is an arithmetic number, because the mean of its divisors is an integer number (5282460606).

Almost surely, 2^21102112211 is an apocalyptic number.

21102112211 is a deficient number, since it is larger than the sum of its proper divisors (27730213).

21102112211 is an equidigital number, since it uses as much as digits as its factorization.

21102112211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27730212.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21102112211 its reverse (11221120112), we get a palindrome (32323232323).

The spelling of 21102112211 in words is "twenty-one billion, one hundred two million, one hundred twelve thousand, two hundred eleven".