20021122121 has 24 divisors (see below), whose sum is σ = 27361543104.
Its totient is φ = 14400802080.
The previous prime is 20021122097. The next prime is 20021122157. The reversal of 20021122121 is 12122112002.
Adding to 20021122121 its reverse (12122112002), we get a palindrome (32143234123).
It is not a de Polignac number, because 20021122121 - 218 = 20020859977 is a prime.
It is a junction number, because it is equal to n+sod(n) for n = 20021122096 and 20021122105.
It is not an unprimeable number, because it can be changed into a prime (20021122021) by changing a digit.
It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1421645 + ... + 1435658.
It is an arithmetic number, because the mean of its divisors is an integer number (1140064296).
Almost surely, 220021122121 is an apocalyptic number.
It is an amenable number.
20021122121 is a deficient number, since it is larger than the sum of its proper divisors (7340420983).
20021122121 is a wasteful number, since it uses less digits than its factorization.
20021122121 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 2857341 (or 2857334 counting only the distinct ones).
The product of its (nonzero) digits is 32, while the sum is 14.
The spelling of 20021122121 in words is "twenty billion, twenty-one million, one hundred twenty-two thousand, one hundred twenty-one".