21112121221011 has 32 divisors (see below), whose sum is σ = 32640401456640. Its totient is φ = 13461438276000.

The previous prime is 21112121221007. The next prime is 21112121221033. The reversal of 21112121221011 is 11012212121112.

It is a happy number.

21112121221011 is a `hidden beast` number, since 211 + 1 + 21 + 212 + 210 + 11 = 666.

It is not a de Polignac number, because 21112121221011 - 2² = 21112121221007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21112121221001) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4431676 + ... + 7865366.

It is an arithmetic number, because the mean of its divisors is an integer number (1020012545520).

Almost surely, 2^{21112121221011} is an apocalyptic number.

21112121221011 is a deficient number, since it is larger than the sum of its proper divisors (11528280235629).

21112121221011 is a wasteful number, since it uses less digits than its factorization.

21112121221011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3443624 (or 3443618 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 21112121221011 its reverse (11012212121112), we get a palindrome (32124333342123).

The spelling of 21112121221011 in words is "twenty-one trillion, one hundred twelve billion, one hundred twenty-one million, two hundred twenty-one thousand, eleven".