20021100222121 has 4 divisors (see below), whose sum is σ = 20215479836032. Its totient is φ = 19826720608212.

The previous prime is 20021100222037. The next prime is 20021100222127. The reversal of 20021100222121 is 12122200112002.

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.

It is a cyclic number.

It is not a de Polignac number, because 20021100222121 - 2⁹ = 20021100221609 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20021100222095 and 20021100222104.

It is not an unprimeable number, because it can be changed into a prime (20021100222127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97189806801 + ... + 97189807006.

It is an arithmetic number, because the mean of its divisors is an integer number (5053869959008).

Almost surely, 2^{20021100222121} is an apocalyptic number.

It is an amenable number.

20021100222121 is a deficient number, since it is larger than the sum of its proper divisors (194379613911).

20021100222121 is a wasteful number, since it uses less digits than its factorization.

20021100222121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194379613910.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 20021100222121 its reverse (12122200112002), we get a palindrome (32143300334123).

The spelling of 20021100222121 in words is "twenty trillion, twenty-one billion, one hundred million, two hundred twenty-two thousand, one hundred twenty-one".