128040 has 64 divisors (see below), whose sum is σ = 423360. Its totient is φ = 30720.

The previous prime is 128033. The next prime is 128047. The reversal of 128040 is 40821.

128040 = T₁₅₅ + T₁₅₆ + ... + T₁₆₄.

It is an interprime number because it is at equal distance from previous prime (128033) and next prime (128047).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128047) by changing a digit.

128040 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1272 + ... + 1368.

It is an arithmetic number, because the mean of its divisors is an integer number (6615).

2¹²⁸⁰⁴⁰ is an apocalyptic number.

128040 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 128040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (211680).

128040 is an abundant number, since it is smaller than the sum of its proper divisors (295320).

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

128040 is a wasteful number, since it uses less digits than its factorization.

128040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 128040 is about 357.8267737328. The cubic root of 128040 is about 50.4020911201.

Adding to 128040 its reverse (40821), we get a palindrome (168861).

The spelling of 128040 in words is "one hundred twenty-eight thousand, forty".