128684 has 12 divisors (see below), whose sum is σ = 229824. Its totient is φ = 63024.

The previous prime is 128683. The next prime is 128693. The reversal of 128684 is 486821.

It is not an unprimeable number, because it can be changed into a prime (128683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 92 + ... + 515.

It is an arithmetic number, because the mean of its divisors is an integer number (19152).

2¹²⁸⁶⁸⁴ is an apocalyptic number.

It is an amenable number.

128684 is a deficient number, since it is larger than the sum of its proper divisors (101140).

128684 is a wasteful number, since it uses less digits than its factorization.

128684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 664 (or 662 counting only the distinct ones).

The product of its digits is 3072, while the sum is 29.

The square root of 128684 is about 358.7255218130. The cubic root of 128684 is about 50.4864519419.

The spelling of 128684 in words is "one hundred twenty-eight thousand, six hundred eighty-four".