205128 has 96 divisors (see below), whose sum is σ = 711360. Its totient is φ = 51840.

The previous prime is 205111. The next prime is 205129. The reversal of 205128 is 821502.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a self number, because there is not a number n which added to its sum of digits gives 205128.

It is not an unprimeable number, because it can be changed into a prime (205129) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5526 + ... + 5562.

It is an arithmetic number, because the mean of its divisors is an integer number (7410).

2²⁰⁵¹²⁸ is an apocalyptic number.

205128 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (355680).

205128 is an abundant number, since it is smaller than the sum of its proper divisors (506232).

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

205128 is a wasteful number, since it uses less digits than its factorization.

205128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 205128 is about 452.9105872024. The cubic root of 205128 is about 58.9759549630.

It can be divided in two parts, 205 and 128, that added together give a palindrome (333).

The spelling of 205128 in words is "two hundred five thousand, one hundred twenty-eight".