128556 has 18 divisors (see below), whose sum is σ = 325052. Its totient is φ = 42840.

The previous prime is 128551. The next prime is 128563. The reversal of 128556 is 655821.

It is a tau number, because it is divible by the number of its divisors (18).

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (128551) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1750 + ... + 1821.

2¹²⁸⁵⁵⁶ is an apocalyptic number.

It is an amenable number.

128556 is an abundant number, since it is smaller than the sum of its proper divisors (196496).

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

128556 is a wasteful number, since it uses less digits than its factorization.

128556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3581 (or 3576 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 128556 is about 358.5470680399. The cubic root of 128556 is about 50.4697070224.

The spelling of 128556 in words is "one hundred twenty-eight thousand, five hundred fifty-six".