20112111121 has 4 divisors (see below), whose sum is σ = 20412291952. Its totient is φ = 19811930292.

The previous prime is 20112111109. The next prime is 20112111157. The reversal of 20112111121 is 12111121102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12111121102 = 2 ⋅6055560551.

It is a cyclic number.

It is not a de Polignac number, because 20112111121 - 2²⁵ = 20078556689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20112111221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 150090315 + ... + 150090448.

It is an arithmetic number, because the mean of its divisors is an integer number (5103072988).

Almost surely, 2^20112111121 is an apocalyptic number.

It is an amenable number.

20112111121 is a deficient number, since it is larger than the sum of its proper divisors (300180831).

20112111121 is an equidigital number, since it uses as much as digits as its factorization.

20112111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 300180830.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 20112111121 its reverse (12111121102), we get a palindrome (32223232223).

The spelling of 20112111121 in words is "twenty billion, one hundred twelve million, one hundred eleven thousand, one hundred twenty-one".