22122220 has 36 divisors (see below), whose sum is σ = 48045312. Its totient is φ = 8556000.

The previous prime is 22122203. The next prime is 22122223. The reversal of 22122220 is 2222122.

It is a self number, because there is not a number n which added to its sum of digits gives 22122220.

It is not an unprimeable number, because it can be changed into a prime (22122223) 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 11 ways as a sum of consecutive naturals, for example, 18645 + ... + 19795.

It is an arithmetic number, because the mean of its divisors is an integer number (1334592).

Almost surely, 2^22122220 is an apocalyptic number.

22122220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22122220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24022656).

22122220 is an abundant number, since it is smaller than the sum of its proper divisors (25923092).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

22122220 is a wasteful number, since it uses less digits than its factorization.

22122220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1222 (or 1189 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 22122220 is about 4703.4264106075. The cubic root of 22122220 is about 280.7218618742.

Adding to 22122220 its reverse (2222122), we get a palindrome (24344342).

The spelling of 22122220 in words is "twenty-two million, one hundred twenty-two thousand, two hundred twenty".