22218406 has 16 divisors (see below), whose sum is σ = 38658816. Its totient is φ = 9379656.

The previous prime is 22218403. The next prime is 22218407. The reversal of 22218406 is 60481222.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22218403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10906 + ... + 12781.

It is an arithmetic number, because the mean of its divisors is an integer number (2416176).

Almost surely, 2^22218406 is an apocalyptic number.

22218406 is a deficient number, since it is larger than the sum of its proper divisors (16440410).

22218406 is a wasteful number, since it uses less digits than its factorization.

22218406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23763.

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 22218406 is about 4713.6404190392. The cubic root of 22218406 is about 281.1281272135.

Adding to 22218406 its reverse (60481222), we get a palindrome (82699628).

The spelling of 22218406 in words is "twenty-two million, two hundred eighteen thousand, four hundred six".