128887905 has 16 divisors (see below), whose sum is σ = 206365824. Its totient is φ = 68691840.

The previous prime is 128887903. The next prime is 128887907. The reversal of 128887905 is 509788821.

It is an interprime number because it is at equal distance from previous prime (128887903) and next prime (128887907).

It is not a de Polignac number, because 128887905 - 2¹ = 128887903 is a prime.

It is a super-2 number, since 2×128887905² = 33224184110578050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (128887901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32332 + ... + 36098.

It is an arithmetic number, because the mean of its divisors is an integer number (12897864).

Almost surely, 2^128887905 is an apocalyptic number.

128887905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128887905 is a deficient number, since it is larger than the sum of its proper divisors (77477919).

128887905 is a wasteful number, since it uses less digits than its factorization.

128887905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6056.

The product of its (nonzero) digits is 322560, while the sum is 48.

The square root of 128887905 is about 11352.8809119095. The cubic root of 128887905 is about 505.1310381122.

The spelling of 128887905 in words is "one hundred twenty-eight million, eight hundred eighty-seven thousand, nine hundred five".