128538 has 24 divisors (see below), whose sum is σ = 287508. Its totient is φ = 41472.

The previous prime is 128521. The next prime is 128549. The reversal of 128538 is 835821.

It is a happy number.

128538 is a `hidden beast` number, since 128 + 538 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 127449 + 1089 = 357^2 + 33^2 .

It is a Curzon number.

It is a plaindrome in base 13.

It is a nialpdrome in base 11.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 570 + ... + 762.

2¹²⁸⁵³⁸ is an apocalyptic number.

128538 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 128538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143754).

128538 is an abundant number, since it is smaller than the sum of its proper divisors (158970).

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

128538 is a wasteful number, since it uses less digits than its factorization.

128538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238 (or 235 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 128538 is about 358.5219658543. The cubic root of 128538 is about 50.4673513768.

It can be divided in two parts, 128 and 538, that added together give a palindrome (666).

The spelling of 128538 in words is "one hundred twenty-eight thousand, five hundred thirty-eight".