128388440 has 32 divisors (see below), whose sum is σ = 289226160. Its totient is φ = 51292800.

The previous prime is 128388439. The next prime is 128388451. The reversal of 128388440 is 44883821.

It is a junction number, because it is equal to n+sod(n) for n = 128388394 and 128388403.

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, 45470 + ... + 48210.

Almost surely, 2^128388440 is an apocalyptic number.

128388440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128388440 is an abundant number, since it is smaller than the sum of its proper divisors (160837720).

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

128388440 is a wasteful number, since it uses less digits than its factorization.

128388440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3923 (or 3919 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 38.

The square root of 128388440 is about 11330.8622796326. The cubic root of 128388440 is about 504.4777006904.

The spelling of 128388440 in words is "one hundred twenty-eight million, three hundred eighty-eight thousand, four hundred forty".