21222222213 has 4 divisors (see below), whose sum is σ = 28296296288. Its totient is φ = 14148148140.

The previous prime is 21222222209. The next prime is 21222222223. The reversal of 21222222213 is 31222222212.

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 not a de Polignac number, because 21222222213 - 2² = 21222222209 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21222222213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222222223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3537037033 + ... + 3537037038.

It is an arithmetic number, because the mean of its divisors is an integer number (7074074072).

Almost surely, 2^21222222213 is an apocalyptic number.

It is an amenable number.

21222222213 is a deficient number, since it is larger than the sum of its proper divisors (7074074075).

21222222213 is an equidigital number, since it uses as much as digits as its factorization.

21222222213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7074074074.

The product of its digits is 768, while the sum is 21.

Adding to 21222222213 its reverse (31222222212), we get a palindrome (52444444425).

Subtracting 21222222213 from its reverse (31222222212), we obtain a palindrome (9999999999).

The spelling of 21222222213 in words is "twenty-one billion, two hundred twenty-two million, two hundred twenty-two thousand, two hundred thirteen".