22012121021 has 4 divisors (see below), whose sum is σ = 24013222944.
Its totient is φ = 20011019100.
The previous prime is 22012121017. The next prime is 22012121029. The reversal of 22012121021 is 12012121022.
Adding to 22012121021 its reverse (12012121022), we get a palindrome (34024242043).
Subtracting from 22012121021 its reverse (12012121022), we obtain a palindrome (9999999999).
It can be divided in two parts, 220121 and 21021, that added together give a palindrome (241142).
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 22012121021 - 22 = 22012121017 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 = 22012120987 and 22012121005.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (22012121029) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1000550945 + ... + 1000550966.
It is an arithmetic number, because the mean of its divisors is an integer number (6003305736).
Almost surely, 222012121021 is an apocalyptic number.
It is an amenable number.
22012121021 is a deficient number, since it is larger than the sum of its proper divisors (2001101923).
22012121021 is a wasteful number, since it uses less digits than its factorization.
22012121021 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 2001101922.
The product of its (nonzero) digits is 32, while the sum is 14.
The spelling of 22012121021 in words is "twenty-two billion, twelve million, one hundred twenty-one thousand, twenty-one".