128435873 has 4 divisors (see below), whose sum is σ = 128800068. Its totient is φ = 128071680.

The previous prime is 128435869. The next prime is 128435893. The reversal of 128435873 is 378534821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20857489 + 107578384 = 4567^2 + 10372^2 .

It is a cyclic number.

It is not a de Polignac number, because 128435873 - 2² = 128435869 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 128435873.

It is not an unprimeable number, because it can be changed into a prime (128435863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 181568 + ... + 182273.

It is an arithmetic number, because the mean of its divisors is an integer number (32200017).

Almost surely, 2^128435873 is an apocalyptic number.

It is an amenable number.

128435873 is a deficient number, since it is larger than the sum of its proper divisors (364195).

128435873 is an equidigital number, since it uses as much as digits as its factorization.

128435873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364194.

The product of its digits is 161280, while the sum is 41.

The square root of 128435873 is about 11332.9551750636. The cubic root of 128435873 is about 504.5398193270.

The spelling of 128435873 in words is "one hundred twenty-eight million, four hundred thirty-five thousand, eight hundred seventy-three".