128381664 has 96 divisors (see below), whose sum is σ = 351267840. Its totient is φ = 41011200.

The previous prime is 128381663. The next prime is 128381677. The reversal of 128381664 is 466183821.

It is a tau number, because it is divible by the number of its divisors (96).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128381663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 532584 + ... + 532824.

It is an arithmetic number, because the mean of its divisors is an integer number (3659040).

Almost surely, 2^128381664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128381664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175633920).

128381664 is an abundant number, since it is smaller than the sum of its proper divisors (222886176).

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

128381664 is a wasteful number, since it uses less digits than its factorization.

128381664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464 (or 456 counting only the distinct ones).

The product of its digits is 55296, while the sum is 39.

The square root of 128381664 is about 11330.5632693172. The cubic root of 128381664 is about 504.4688255376.

The spelling of 128381664 in words is "one hundred twenty-eight million, three hundred eighty-one thousand, six hundred sixty-four".