128128736 has 12 divisors (see below), whose sum is σ = 252253512. Its totient is φ = 64064352.

The previous prime is 128128727. The next prime is 128128739. The reversal of 128128736 is 637821821.

It is a self number, because there is not a number n which added to its sum of digits gives 128128736.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128128739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2001980 + ... + 2002043.

It is an arithmetic number, because the mean of its divisors is an integer number (21021126).

Almost surely, 2^128128736 is an apocalyptic number.

128128736 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

128128736 is a deficient number, since it is larger than the sum of its proper divisors (124124776).

128128736 is an equidigital number, since it uses as much as digits as its factorization.

128128736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4004033 (or 4004025 counting only the distinct ones).

The product of its digits is 32256, while the sum is 38.

The square root of 128128736 is about 11319.3964503413. The cubic root of 128128736 is about 504.1373187601.

The spelling of 128128736 in words is "one hundred twenty-eight million, one hundred twenty-eight thousand, seven hundred thirty-six".