128583440 has 20 divisors (see below), whose sum is σ = 298956684. Its totient is φ = 51433344.

The previous prime is 128583439. The next prime is 128583463. The reversal of 128583440 is 44385821.

It can be written as a sum of positive squares in 2 ways, for example, as 52823824 + 75759616 = 7268^2 + 8704^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 128583440.

It is an unprimeable number.

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, 803567 + ... + 803726.

Almost surely, 2^128583440 is an apocalyptic number.

128583440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128583440 is an abundant number, since it is smaller than the sum of its proper divisors (170373244).

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

128583440 is a wasteful number, since it uses less digits than its factorization.

128583440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1607306 (or 1607300 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 35.

The square root of 128583440 is about 11339.4638321219. The cubic root of 128583440 is about 504.7329765019.

The spelling of 128583440 in words is "one hundred twenty-eight million, five hundred eighty-three thousand, four hundred forty".