128340239 has 4 divisors (see below), whose sum is σ = 130147920. Its totient is φ = 126532560.

The previous prime is 128340227. The next prime is 128340241. The reversal of 128340239 is 932043821.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 128340239 - 2²⁰ = 127291663 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128340139) 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, 903734 + ... + 903875.

It is an arithmetic number, because the mean of its divisors is an integer number (32536980).

Almost surely, 2^128340239 is an apocalyptic number.

128340239 is a deficient number, since it is larger than the sum of its proper divisors (1807681).

128340239 is an equidigital number, since it uses as much as digits as its factorization.

128340239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1807680.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 128340239 is about 11328.7351015018. The cubic root of 128340239 is about 504.4145605995.

The spelling of 128340239 in words is "one hundred twenty-eight million, three hundred forty thousand, two hundred thirty-nine".