21011110211 has 16 divisors (see below), whose sum is σ = 26097086400. Its totient is φ = 16471651968.

The previous prime is 21011110201. The next prime is 21011110231. The reversal of 21011110211 is 11201111012.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21011110211 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21011110192 and 21011110201.

It is not an unprimeable number, because it can be changed into a prime (21011110201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1049216 + ... + 1069053.

It is an arithmetic number, because the mean of its divisors is an integer number (1631067900).

Almost surely, 2^21011110211 is an apocalyptic number.

21011110211 is a deficient number, since it is larger than the sum of its proper divisors (5085976189).

21011110211 is a wasteful number, since it uses less digits than its factorization.

21011110211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2118398.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 21011110211 its reverse (11201111012), we get a palindrome (32212221223).

The spelling of 21011110211 in words is "twenty-one billion, eleven million, one hundred ten thousand, two hundred eleven".