128996775 has 72 divisors (see below), whose sum is σ = 241155200. Its totient is φ = 65862720.

The previous prime is 128996773. The next prime is 128996779. The reversal of 128996775 is 577699821.

It is not a de Polignac number, because 128996775 - 2¹ = 128996773 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128996771) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 648126 + ... + 648324.

Almost surely, 2^128996775 is an apocalyptic number.

128996775 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128996775 is a deficient number, since it is larger than the sum of its proper divisors (112158425).

128996775 is a wasteful number, since it uses less digits than its factorization.

128996775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325 (or 317 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 54.

The square root of 128996775 is about 11357.6747180046. The cubic root of 128996775 is about 505.2732240405.

The spelling of 128996775 in words is "one hundred twenty-eight million, nine hundred ninety-six thousand, seven hundred seventy-five".