20011122121 has 4 divisors (see below), whose sum is σ = 20099277072. Its totient is φ = 19922967172.

The previous prime is 20011122029. The next prime is 20011122137. The reversal of 20011122121 is 12122111002.

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 a cyclic number.

It is not a de Polignac number, because 20011122121 - 2⁹ = 20011121609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20011122151) 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, 44077135 + ... + 44077588.

It is an arithmetic number, because the mean of its divisors is an integer number (5024819268).

Almost surely, 2^20011122121 is an apocalyptic number.

It is an amenable number.

20011122121 is a deficient number, since it is larger than the sum of its proper divisors (88154951).

20011122121 is an equidigital number, since it uses as much as digits as its factorization.

20011122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88154950.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20011122121 its reverse (12122111002), we get a palindrome (32133233123).

The spelling of 20011122121 in words is "twenty billion, eleven million, one hundred twenty-two thousand, one hundred twenty-one".