128775136 has 72 divisors (see below), whose sum is σ = 312330816. Its totient is φ = 51932160.

The previous prime is 128775131. The next prime is 128775149. The reversal of 128775136 is 631577821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128775131) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24241 + ... + 29071.

It is an arithmetic number, because the mean of its divisors is an integer number (4337928).

Almost surely, 2^128775136 is an apocalyptic number.

128775136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128775136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156165408).

128775136 is an abundant number, since it is smaller than the sum of its proper divisors (183555680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128775136 is a wasteful number, since it uses less digits than its factorization.

128775136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4872 (or 4857 counting only the distinct ones).

The product of its digits is 70560, while the sum is 40.

The square root of 128775136 is about 11347.9132883539. The cubic root of 128775136 is about 504.9836755825.

The spelling of 128775136 in words is "one hundred twenty-eight million, seven hundred seventy-five thousand, one hundred thirty-six".