22128820 has 48 divisors (see below), whose sum is σ = 53399808. Its totient is φ = 7545600.

The previous prime is 22128811. The next prime is 22128839. The reversal of 22128820 is 2882122.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 36520 + ... + 37120.

It is an arithmetic number, because the mean of its divisors is an integer number (1112496).

Almost surely, 2^22128820 is an apocalyptic number.

22128820 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 22128820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26699904).

22128820 is an abundant number, since it is smaller than the sum of its proper divisors (31270988).

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

22128820 is a wasteful number, since it uses less digits than its factorization.

22128820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 880 (or 878 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 25.

The square root of 22128820 is about 4704.1279744497. The cubic root of 22128820 is about 280.7497761924.

The spelling of 22128820 in words is "twenty-two million, one hundred twenty-eight thousand, eight hundred twenty".