128305 has 8 divisors (see below), whose sum is σ = 156672. Its totient is φ = 100848.

The previous prime is 128291. The next prime is 128311. The reversal of 128305 is 503821.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128305 - 2⁵ = 128273 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 144 + ... + 526.

It is an arithmetic number, because the mean of its divisors is an integer number (19584).

2¹²⁸³⁰⁵ is an apocalyptic number.

It is an amenable number.

128305 is a deficient number, since it is larger than the sum of its proper divisors (28367).

128305 is an equidigital number, since it uses as much as digits as its factorization.

128305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 455.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 128305 is about 358.1968732415. The cubic root of 128305 is about 50.4368389858.

The spelling of 128305 in words is "one hundred twenty-eight thousand, three hundred five".