128889 has 6 divisors (see below), whose sum is σ = 186186. Its totient is φ = 85920.

The previous prime is 128879. The next prime is 128903. The reversal of 128889 is 988821.

It can be written as a sum of positive squares in only one way, i.e., 71289 + 57600 = 267^2 + 240^2 .

It is not a de Polignac number, because 128889 - 2⁴ = 128873 is a prime.

It is a super-2 number, since 2×128889² = 33224748642, which contains 22 as substring.

128889 is a lucky number.

It is a plaindrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128819) 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, 7152 + ... + 7169.

It is an arithmetic number, because the mean of its divisors is an integer number (31031).

2¹²⁸⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

128889 is a deficient number, since it is larger than the sum of its proper divisors (57297).

128889 is a wasteful number, since it uses less digits than its factorization.

128889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14327 (or 14324 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 128889 is about 359.0111418884. The cubic root of 128889 is about 50.5132468598.

The spelling of 128889 in words is "one hundred twenty-eight thousand, eight hundred eighty-nine".