128287439 has 6 divisors (see below), whose sum is σ = 149232384. Its totient is φ = 109960620.

The previous prime is 128287429. The next prime is 128287463. The reversal of 128287439 is 934782821.

It is a de Polignac number, because none of the positive numbers 2^k-128287439 is a prime.

It is a super-3 number, since 3×128287439³ (a number of 25 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 128287439.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128287429) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1309007 + ... + 1309104.

It is an arithmetic number, because the mean of its divisors is an integer number (24872064).

Almost surely, 2^128287439 is an apocalyptic number.

128287439 is a deficient number, since it is larger than the sum of its proper divisors (20944945).

128287439 is an equidigital number, since it uses as much as digits as its factorization.

128287439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2618125 (or 2618118 counting only the distinct ones).

The product of its digits is 193536, while the sum is 44.

The square root of 128287439 is about 11326.4045045195. The cubic root of 128287439 is about 504.3453779794.

The spelling of 128287439 in words is "one hundred twenty-eight million, two hundred eighty-seven thousand, four hundred thirty-nine".