21223222 has 4 divisors (see below), whose sum is σ = 31834836. Its totient is φ = 10611610.

The previous prime is 21223219. The next prime is 21223261. The reversal of 21223222 is 22232212.

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

It is a super-2 number, since 2×21223222² = 900850304122568, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21223196 and 21223205.

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, 5305804 + ... + 5305807.

It is an arithmetic number, because the mean of its divisors is an integer number (7958709).

Almost surely, 2^21223222 is an apocalyptic number.

21223222 is a deficient number, since it is larger than the sum of its proper divisors (10611614).

21223222 is a wasteful number, since it uses less digits than its factorization.

21223222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10611613.

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

The square root of 21223222 is about 4606.8668311554. The cubic root of 21223222 is about 276.8665180749.

Adding to 21223222 its reverse (22232212), we get a palindrome (43455434).

The spelling of 21223222 in words is "twenty-one million, two hundred twenty-three thousand, two hundred twenty-two".