21322213 has 4 divisors (see below), whose sum is σ = 23260608. Its totient is φ = 19383820.

The previous prime is 21322207. The next prime is 21322229. The reversal of 21322213 is 31222312.

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 21322213 - 2⁵ = 21322181 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21320213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 969181 + ... + 969202.

It is an arithmetic number, because the mean of its divisors is an integer number (5815152).

Almost surely, 2^21322213 is an apocalyptic number.

It is an amenable number.

21322213 is a deficient number, since it is larger than the sum of its proper divisors (1938395).

21322213 is a wasteful number, since it uses less digits than its factorization.

21322213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1938394.

The product of its digits is 144, while the sum is 16.

The square root of 21322213 is about 4617.5981852041. The cubic root of 21322213 is about 277.2963113115.

Adding to 21322213 its reverse (31222312), we get a palindrome (52544525).

Subtracting 21322213 from its reverse (31222312), we obtain a palindrome (9900099).

The spelling of 21322213 in words is "twenty-one million, three hundred twenty-two thousand, two hundred thirteen".