128985 has 8 divisors (see below), whose sum is σ = 206400. Its totient is φ = 68784.

The previous prime is 128983. The next prime is 128987. The reversal of 128985 is 589821.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (128983) and next prime (128987).

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

It is not a de Polignac number, because 128985 - 2¹ = 128983 is a prime.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128981) 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, 4285 + ... + 4314.

It is an arithmetic number, because the mean of its divisors is an integer number (25800).

2¹²⁸⁹⁸⁵ is an apocalyptic number.

128985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128985 is a deficient number, since it is larger than the sum of its proper divisors (77415).

128985 is an equidigital number, since it uses as much as digits as its factorization.

128985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8607.

The product of its digits is 5760, while the sum is 33.

The square root of 128985 is about 359.1448175876. The cubic root of 128985 is about 50.5257849565.

The spelling of 128985 in words is "one hundred twenty-eight thousand, nine hundred eighty-five".