128643136 has 28 divisors (see below), whose sum is σ = 260713728. Its totient is φ = 62951552.

The previous prime is 128643121. The next prime is 128643139. The reversal of 128643136 is 631346821.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (128643139) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18376 + ... + 24391.

Almost surely, 2^128643136 is an apocalyptic number.

128643136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

128643136 is an abundant number, since it is smaller than the sum of its proper divisors (132070592).

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

128643136 is an equidigital number, since it uses as much as digits as its factorization.

128643136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42826 (or 42816 counting only the distinct ones).

The product of its digits is 20736, while the sum is 34.

The square root of 128643136 is about 11342.0957499044. The cubic root of 128643136 is about 504.8110733345.

Adding to 128643136 its reverse (631346821), we get a palindrome (759989957).

The spelling of 128643136 in words is "one hundred twenty-eight million, six hundred forty-three thousand, one hundred thirty-six".