128941866 has 48 divisors (see below), whose sum is σ = 295844640. Its totient is φ = 40474080.

The previous prime is 128941829. The next prime is 128941867. The reversal of 128941866 is 668149821.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (128941867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 60861 + ... + 62943.

It is an arithmetic number, because the mean of its divisors is an integer number (6163430).

Almost surely, 2^128941866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128941866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147922320).

128941866 is an abundant number, since it is smaller than the sum of its proper divisors (166902774).

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

128941866 is a wasteful number, since it uses less digits than its factorization.

128941866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2291 (or 2288 counting only the distinct ones).

The product of its digits is 165888, while the sum is 45.

The square root of 128941866 is about 11355.2571965588. The cubic root of 128941866 is about 505.2015220285.

The spelling of 128941866 in words is "one hundred twenty-eight million, nine hundred forty-one thousand, eight hundred sixty-six".