128935566 has 48 divisors (see below), whose sum is σ = 291236400. Its totient is φ = 41174784.

The previous prime is 128935561. The next prime is 128935579. The reversal of 128935566 is 665539821.

128935566 is a `hidden beast` number, since 1 + 2 + 8 + 93 + 556 + 6 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128935561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 71670 + ... + 73446.

It is an arithmetic number, because the mean of its divisors is an integer number (6067425).

Almost surely, 2^128935566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128935566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145618200).

128935566 is an abundant number, since it is smaller than the sum of its proper divisors (162300834).

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

128935566 is a wasteful number, since it uses less digits than its factorization.

128935566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1953 (or 1950 counting only the distinct ones).

The product of its digits is 388800, while the sum is 45.

The square root of 128935566 is about 11354.9797886214. The cubic root of 128935566 is about 505.1932939758.

The spelling of 128935566 in words is "one hundred twenty-eight million, nine hundred thirty-five thousand, five hundred sixty-six".