22021022221 has 4 divisors (see below), whose sum is σ = 24022933344. Its totient is φ = 20019111100.

The previous prime is 22021022209. The next prime is 22021022237. The reversal of 22021022221 is 12222012022.

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 22021022221 - 2²¹ = 22018925069 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22021022195 and 22021022204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021022251) 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, 1000955545 + ... + 1000955566.

It is an arithmetic number, because the mean of its divisors is an integer number (6005733336).

Almost surely, 2^22021022221 is an apocalyptic number.

It is an amenable number.

22021022221 is a deficient number, since it is larger than the sum of its proper divisors (2001911123).

22021022221 is a wasteful number, since it uses less digits than its factorization.

22021022221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2001911122.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 22021022221 its reverse (12222012022), we get a palindrome (34243034243).

The spelling of 22021022221 in words is "twenty-two billion, twenty-one million, twenty-two thousand, two hundred twenty-one".