128506 has 16 divisors (see below), whose sum is σ = 225216. Its totient is φ = 53856.

The previous prime is 128489. The next prime is 128509. The reversal of 128506 is 605821.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128509) 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 7 ways as a sum of consecutive naturals, for example, 870 + ... + 1006.

It is an arithmetic number, because the mean of its divisors is an integer number (14076).

2¹²⁸⁵⁰⁶ is an apocalyptic number.

128506 is a deficient number, since it is larger than the sum of its proper divisors (96710).

128506 is a wasteful number, since it uses less digits than its factorization.

128506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 128506 is about 358.4773354063. The cubic root of 128506 is about 50.4631630193.

The spelling of 128506 in words is "one hundred twenty-eight thousand, five hundred six".