20111112121221 has 24 divisors (see below), whose sum is σ = 31692544004160. Its totient is φ = 12187665600000.

The previous prime is 20111112121189. The next prime is 20111112121297. The reversal of 20111112121221 is 12212121111102.

It is a happy number.

20111112121221 is a `hidden beast` number, since 201 + 11 + 112 + 121 + 221 = 666.

It is not a de Polignac number, because 20111112121221 - 2⁵ = 20111112121189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20111112121194 and 20111112121203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111112121621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6025116 + ... + 8747813.

It is an arithmetic number, because the mean of its divisors is an integer number (1320522666840).

Almost surely, 2^{20111112121221} is an apocalyptic number.

It is an amenable number.

20111112121221 is a deficient number, since it is larger than the sum of its proper divisors (11581431882939).

20111112121221 is a wasteful number, since it uses less digits than its factorization.

20111112121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14786697 (or 14786694 counting only the distinct ones).

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

Adding to 20111112121221 its reverse (12212121111102), we get a palindrome (32323233232323).

The spelling of 20111112121221 in words is "twenty trillion, one hundred eleven billion, one hundred twelve million, one hundred twenty-one thousand, two hundred twenty-one".