128439135 has 32 divisors (see below), whose sum is σ = 249096960. Its totient is φ = 62272800.

The previous prime is 128439133. The next prime is 128439137. The reversal of 128439135 is 531934821.

It is an interprime number because it is at equal distance from previous prime (128439133) and next prime (128439137).

It is not a de Polignac number, because 128439135 - 2¹ = 128439133 is a prime.

It is a super-2 number, since 2×128439135² = 32993222799096450, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 128439135.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128439133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 41761 + ... + 44730.

It is an arithmetic number, because the mean of its divisors is an integer number (7784280).

Almost surely, 2^128439135 is an apocalyptic number.

128439135 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128439135 is a deficient number, since it is larger than the sum of its proper divisors (120657825).

128439135 is a wasteful number, since it uses less digits than its factorization.

128439135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86516 (or 86510 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 128439135 is about 11333.0990907165. The cubic root of 128439135 is about 504.5440907062.

The spelling of 128439135 in words is "one hundred twenty-eight million, four hundred thirty-nine thousand, one hundred thirty-five".