21111112211211 has 48 divisors (see below), whose sum is σ = 34675002855168. Its totient is φ = 12263009774400.

The previous prime is 21111112211051. The next prime is 21111112211261. The reversal of 21111112211211 is 11211221111112.

21111112211211 is a `hidden beast` number, since 21 + 111 + 112 + 211 + 211 = 666.

It is not a de Polignac number, because 21111112211211 - 2¹⁴ = 21111112194827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21111112211261) 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 47 ways as a sum of consecutive naturals, for example, 42764575 + ... + 43255416.

It is an arithmetic number, because the mean of its divisors is an integer number (722395892816).

Almost surely, 2^{21111112211211} is an apocalyptic number.

21111112211211 is a deficient number, since it is larger than the sum of its proper divisors (13563890643957).

21111112211211 is a wasteful number, since it uses less digits than its factorization.

21111112211211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86020112 (or 86020109 counting only the distinct ones).

The product of its digits is 16, while the sum is 18.

Adding to 21111112211211 its reverse (11211221111112), we get a palindrome (32322333322323).

The spelling of 21111112211211 in words is "twenty-one trillion, one hundred eleven billion, one hundred twelve million, two hundred eleven thousand, two hundred eleven".