22121220222221 has 4 divisors (see below), whose sum is σ = 22123262631744. Its totient is φ = 22119177812700.

The previous prime is 22121220222197. The next prime is 22121220222313. The reversal of 22121220222221 is 12222202212122.

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 a de Polignac number, because none of the positive numbers 2^k-22121220222221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22121220222421) 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, 1021188515 + ... + 1021210176.

It is an arithmetic number, because the mean of its divisors is an integer number (5530815657936).

Almost surely, 2^{22121220222221} is an apocalyptic number.

It is an amenable number.

22121220222221 is a deficient number, since it is larger than the sum of its proper divisors (2042409523).

22121220222221 is a wasteful number, since it uses less digits than its factorization.

22121220222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2042409522.

The product of its (nonzero) digits is 1024, while the sum is 23.

Adding to 22121220222221 its reverse (12222202212122), we get a palindrome (34343422434343).

The spelling of 22121220222221 in words is "twenty-two trillion, one hundred twenty-one billion, two hundred twenty million, two hundred twenty-two thousand, two hundred twenty-one".