128240 has 40 divisors (see below), whose sum is σ = 342240. Its totient is φ = 43776.

The previous prime is 128239. The next prime is 128257. The reversal of 128240 is 42821.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

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, 446 + ... + 674.

It is an arithmetic number, because the mean of its divisors is an integer number (8556).

2¹²⁸²⁴⁰ is an apocalyptic number.

128240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171120).

128240 is an abundant number, since it is smaller than the sum of its proper divisors (214000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128240 is a wasteful number, since it uses less digits than its factorization.

128240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 243 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 128240 is about 358.1061295203. The cubic root of 128240 is about 50.4283203563.

The spelling of 128240 in words is "one hundred twenty-eight thousand, two hundred forty".