128390439 has 8 divisors (see below), whose sum is σ = 178630272. Its totient is φ = 81872120.

The previous prime is 128390413. The next prime is 128390447. The reversal of 128390439 is 934093821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128390439 - 2⁹ = 128389927 is a prime.

It is a super-2 number, since 2×128390439² = 32968209653225442, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 128390397 and 128390406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128397439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 930297 + ... + 930434.

It is an arithmetic number, because the mean of its divisors is an integer number (22328784).

Almost surely, 2^128390439 is an apocalyptic number.

128390439 is a deficient number, since it is larger than the sum of its proper divisors (50239833).

128390439 is a wasteful number, since it uses less digits than its factorization.

128390439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1860757.

The product of its (nonzero) digits is 46656, while the sum is 39.

The square root of 128390439 is about 11330.9504896986. The cubic root of 128390439 is about 504.4803189055.

The spelling of 128390439 in words is "one hundred twenty-eight million, three hundred ninety thousand, four hundred thirty-nine".