128326091 has 4 divisors (see below), whose sum is σ = 130747392. Its totient is φ = 125904792.

The previous prime is 128325983. The next prime is 128326097. The reversal of 128326091 is 190623821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 190623821 = 1301 ⋅146521.

It is a cyclic number.

It is not a de Polignac number, because 128326091 - 2²⁶ = 61217227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128326097) 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, 1210571 + ... + 1210676.

It is an arithmetic number, because the mean of its divisors is an integer number (32686848).

Almost surely, 2^128326091 is an apocalyptic number.

128326091 is a deficient number, since it is larger than the sum of its proper divisors (2421301).

128326091 is an equidigital number, since it uses as much as digits as its factorization.

128326091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2421300.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 128326091 is about 11328.1106544737. The cubic root of 128326091 is about 504.3960246632.

The spelling of 128326091 in words is "one hundred twenty-eight million, three hundred twenty-six thousand, ninety-one".