128799440 has 240 divisors, whose sum is σ = 396938880. Its totient is φ = 38384640.

The previous prime is 128799427. The next prime is 128799481. The reversal of 128799440 is 44997821.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 128799391 and 128799400.

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, 1250429 + ... + 1250531.

It is an arithmetic number, because the mean of its divisors is an integer number (1653912).

Almost surely, 2^128799440 is an apocalyptic number.

128799440 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 128799440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (198469440).

128799440 is an abundant number, since it is smaller than the sum of its proper divisors (268139440).

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

128799440 is a wasteful number, since it uses less digits than its factorization.

128799440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 128799440 is about 11348.9840955039. The cubic root of 128799440 is about 505.0154424582.

The spelling of 128799440 in words is "one hundred twenty-eight million, seven hundred ninety-nine thousand, four hundred forty".