21222223 has 8 divisors (see below), whose sum is σ = 23377536. Its totient is φ = 19104600.

The previous prime is 21222211. The next prime is 21222251. The reversal of 21222223 is 32222212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21222223 - 2¹⁷ = 21091151 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21222197 and 21222206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222293) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8233 + ... + 10498.

It is an arithmetic number, because the mean of its divisors is an integer number (2922192).

Almost surely, 2^21222223 is an apocalyptic number.

21222223 is a deficient number, since it is larger than the sum of its proper divisors (2155313).

21222223 is a wasteful number, since it uses less digits than its factorization.

21222223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18845.

The product of its digits is 192, while the sum is 16.

The square root of 21222223 is about 4606.7584047788. The cubic root of 21222223 is about 276.8621738713.

Adding to 21222223 its reverse (32222212), we get a palindrome (53444435).

The spelling of 21222223 in words is "twenty-one million, two hundred twenty-two thousand, two hundred twenty-three".