128128 has 64 divisors (see below), whose sum is σ = 342720. Its totient is φ = 46080.

The previous prime is 128119. The next prime is 128147. The reversal of 128128 is 821821.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 128099 and 128108.

It is an unprimeable number.

128128 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9850 + ... + 9862.

It is an arithmetic number, because the mean of its divisors is an integer number (5355).

2¹²⁸¹²⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171360).

128128 is an abundant number, since it is smaller than the sum of its proper divisors (214592).

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

128128 is a wasteful number, since it uses less digits than its factorization.

128128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45 (or 33 counting only the distinct ones).

The product of its digits is 256, while the sum is 22.

The square root of 128128 is about 357.9497171392. The cubic root of 128128 is about 50.4136353466.

Adding to 128128 its reverse (821821), we get a palindrome (949949).

It can be divided in two parts, 128 and 128, that added together give a 8-th power (256 = 2⁸).

The spelling of 128128 in words is "one hundred twenty-eight thousand, one hundred twenty-eight".