22221812 has 18 divisors (see below), whose sum is σ = 39562614. Its totient is φ = 10921440.

The previous prime is 22221799. The next prime is 22221817. The reversal of 22221812 is 21812222.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 16 + 22221796 = 4^2 + 4714^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22221817) 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 5 ways as a sum of consecutive naturals, for example, 14138 + ... + 15630.

It is an arithmetic number, because the mean of its divisors is an integer number (2197923).

Almost surely, 2^22221812 is an apocalyptic number.

It is an amenable number.

22221812 is a deficient number, since it is larger than the sum of its proper divisors (17340802).

22221812 is a wasteful number, since it uses less digits than its factorization.

22221812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1619 (or 1556 counting only the distinct ones).

The product of its digits is 256, while the sum is 20.

The square root of 22221812 is about 4714.0016970722. The cubic root of 22221812 is about 281.1424917825.

The spelling of 22221812 in words is "twenty-two million, two hundred twenty-one thousand, eight hundred twelve".