22128665 has 16 divisors (see below), whose sum is σ = 29071056. Its totient is φ = 16070400.

The previous prime is 22128649. The next prime is 22128683. The reversal of 22128665 is 56682122.

It can be written as a sum of positive squares in 8 ways, for example, as 8386816 + 13741849 = 2896^2 + 3707^2 .

It is not a de Polignac number, because 22128665 - 2⁴ = 22128649 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1175 + ... + 6755.

It is an arithmetic number, because the mean of its divisors is an integer number (1816941).

Almost surely, 2^22128665 is an apocalyptic number.

It is an amenable number.

22128665 is a deficient number, since it is larger than the sum of its proper divisors (6942391).

22128665 is a wasteful number, since it uses less digits than its factorization.

22128665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5660.

The product of its digits is 11520, while the sum is 32.

The square root of 22128665 is about 4704.1114995289. Note that the first 3 decimals coincide. The cubic root of 22128665 is about 280.7491206925.

The spelling of 22128665 in words is "twenty-two million, one hundred twenty-eight thousand, six hundred sixty-five".