128855 has 4 divisors (see below), whose sum is σ = 154632. Its totient is φ = 103080.

The previous prime is 128837. The next prime is 128857. The reversal of 128855 is 558821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 558821 = 61 ⋅9161.

It is not a de Polignac number, because 128855 - 2⁸ = 128599 is a prime.

It is a super-2 number, since 2×128855² = 33207222050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128857) 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 3 ways as a sum of consecutive naturals, for example, 12881 + ... + 12890.

It is an arithmetic number, because the mean of its divisors is an integer number (38658).

2¹²⁸⁸⁵⁵ is an apocalyptic number.

128855 is a deficient number, since it is larger than the sum of its proper divisors (25777).

128855 is an equidigital number, since it uses as much as digits as its factorization.

128855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25776.

The product of its digits is 3200, while the sum is 29.

The square root of 128855 is about 358.9637864743. The cubic root of 128855 is about 50.5088047910.

The spelling of 128855 in words is "one hundred twenty-eight thousand, eight hundred fifty-five".