22128289 has 2 divisors, whose sum is σ = 22128290. Its totient is φ = 22128288.

The previous prime is 22128287. The next prime is 22128307. The reversal of 22128289 is 98282122.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22043025 + 85264 = 4695^2 + 292^2 .

It is a cyclic number.

It is not a de Polignac number, because 22128289 - 2¹ = 22128287 is a prime.

It is a super-2 number, since 2×22128289² = 979322348135042, which contains 22 as substring.

Together with 22128287, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (22128283) 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 as a sum of consecutive naturals, namely, 11064144 + 11064145.

It is an arithmetic number, because the mean of its divisors is an integer number (11064145).

Almost surely, 2^22128289 is an apocalyptic number.

It is an amenable number.

22128289 is a deficient number, since it is larger than the sum of its proper divisors (1).

22128289 is an equidigital number, since it uses as much as digits as its factorization.

22128289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 34.

The square root of 22128289 is about 4704.0715343200. The cubic root of 22128289 is about 280.7475305640.

It can be divided in two parts, 2212 and 8289, that added together give a palindrome (10501).

The spelling of 22128289 in words is "twenty-two million, one hundred twenty-eight thousand, two hundred eighty-nine".