20012111121 has 4 divisors (see below), whose sum is σ = 26682814832. Its totient is φ = 13341407412.

The previous prime is 20012111099. The next prime is 20012111129. The reversal of 20012111121 is 12111121002.

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.

It is not a de Polignac number, because 20012111121 - 2⁵ = 20012111089 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20012111097 and 20012111106.

It is not an unprimeable number, because it can be changed into a prime (20012111129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3335351851 + ... + 3335351856.

It is an arithmetic number, because the mean of its divisors is an integer number (6670703708).

Almost surely, 2^20012111121 is an apocalyptic number.

It is an amenable number.

20012111121 is a deficient number, since it is larger than the sum of its proper divisors (6670703711).

20012111121 is an equidigital number, since it uses as much as digits as its factorization.

20012111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6670703710.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 20012111121 its reverse (12111121002), we get a palindrome (32123232123).

The spelling of 20012111121 in words is "twenty billion, twelve million, one hundred eleven thousand, one hundred twenty-one".