128991744 has 320 divisors, whose sum is σ = 460922880. Its totient is φ = 34836480.

The previous prime is 128991721. The next prime is 128991757. The reversal of 128991744 is 447199821.

It is a happy number.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a nude number because it is divisible by every one of its digits.

Its product of digits (145152) is a multiple of the sum of its prime factors (108).

It is a self number, because there is not a number n which added to its sum of digits gives 128991744.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2999787 + ... + 2999829.

It is an arithmetic number, because the mean of its divisors is an integer number (1440384).

Almost surely, 2^128991744 is an apocalyptic number.

128991744 is a gapful number since it is divisible by the number (14) 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 128991744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (230461440).

128991744 is an abundant number, since it is smaller than the sum of its proper divisors (331931136).

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

128991744 is an equidigital number, since it uses as much as digits as its factorization.

128991744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 86 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 128991744 is about 11357.4532356510. The cubic root of 128991744 is about 505.2666552389.

The spelling of 128991744 in words is "one hundred twenty-eight million, nine hundred ninety-one thousand, seven hundred forty-four".