21226222 has 4 divisors (see below), whose sum is σ = 31839336. Its totient is φ = 10613110.

The previous prime is 21226213. The next prime is 21226237. The reversal of 21226222 is 22262212.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21226222.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5306554 + ... + 5306557.

It is an arithmetic number, because the mean of its divisors is an integer number (7959834).

Almost surely, 2^21226222 is an apocalyptic number.

21226222 is a deficient number, since it is larger than the sum of its proper divisors (10613114).

21226222 is a wasteful number, since it uses less digits than its factorization.

21226222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10613113.

The product of its digits is 384, while the sum is 19.

The square root of 21226222 is about 4607.1924205529. The cubic root of 21226222 is about 276.8795629120.

Adding to 21226222 its reverse (22262212), we get a palindrome (43488434).

The spelling of 21226222 in words is "twenty-one million, two hundred twenty-six thousand, two hundred twenty-two".