128693440 has 56 divisors (see below), whose sum is σ = 309250080. Its totient is φ = 51007488.

The previous prime is 128693429. The next prime is 128693443. The reversal of 128693440 is 44396821.

It is a self number, because there is not a number n which added to its sum of digits gives 128693440.

It is not an unprimeable number, because it can be changed into a prime (128693443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34381 + ... + 37939.

Almost surely, 2^128693440 is an apocalyptic number.

128693440 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 128693440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (154625040).

128693440 is an abundant number, since it is smaller than the sum of its proper divisors (180556640).

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

128693440 is a wasteful number, since it uses less digits than its factorization.

128693440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3689 (or 3679 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 37.

The square root of 128693440 is about 11344.3131127451. The cubic root of 128693440 is about 504.8768644000.

The spelling of 128693440 in words is "one hundred twenty-eight million, six hundred ninety-three thousand, four hundred forty".