21122322221 has 32 divisors (see below), whose sum is σ = 28373108736. Its totient is φ = 15185880000.

The previous prime is 21122322209. The next prime is 21122322239. The reversal of 21122322221 is 12222322112.

It is a cyclic number.

It is not a de Polignac number, because 21122322221 - 2¹⁴ = 21122305837 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21122322193 and 21122322202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122322121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3271046 + ... + 3277496.

It is an arithmetic number, because the mean of its divisors is an integer number (886659648).

Almost surely, 2^21122322221 is an apocalyptic number.

It is an amenable number.

21122322221 is a deficient number, since it is larger than the sum of its proper divisors (7250786515).

21122322221 is a wasteful number, since it uses less digits than its factorization.

21122322221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9753.

The product of its digits is 384, while the sum is 20.

Adding to 21122322221 its reverse (12222322112), we get a palindrome (33344644333).

It can be divided in two parts, 21122 and 322221, that added together give a palindrome (343343).

The spelling of 21122322221 in words is "twenty-one billion, one hundred twenty-two million, three hundred twenty-two thousand, two hundred twenty-one".