128287440 has 240 divisors, whose sum is σ = 467970048. Its totient is φ = 31371264.

The previous prime is 128287429. The next prime is 128287463. The reversal of 128287440 is 44782821.

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-3 number, since 3×128287440³ (a number of 25 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 128287395 and 128287404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 575169 + ... + 575391.

Almost surely, 2^128287440 is an apocalyptic number.

128287440 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 128287440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (233985024).

128287440 is an abundant number, since it is smaller than the sum of its proper divisors (339682608).

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

128287440 is a wasteful number, since it uses less digits than its factorization.

128287440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306 (or 297 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 36.

The square root of 128287440 is about 11326.4045486642. The cubic root of 128287440 is about 504.3453792899.

The spelling of 128287440 in words is "one hundred twenty-eight million, two hundred eighty-seven thousand, four hundred forty".