128128388 has 24 divisors (see below), whose sum is σ = 240966432. Its totient is φ = 59393664.

The previous prime is 128128387. The next prime is 128128391. The reversal of 128128388 is 883821821.

It is a super-2 number, since 2×128128388² = 32833767622957088, which contains 22 as substring.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (128128387) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9506 + ... + 18617.

It is an arithmetic number, because the mean of its divisors is an integer number (10040268).

Almost surely, 2^128128388 is an apocalyptic number.

It is an amenable number.

128128388 is a deficient number, since it is larger than the sum of its proper divisors (112838044).

128128388 is a wasteful number, since it uses less digits than its factorization.

128128388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28211 (or 28209 counting only the distinct ones).

The product of its digits is 49152, while the sum is 41.

The square root of 128128388 is about 11319.3810784866. The cubic root of 128128388 is about 504.1368623442.

The spelling of 128128388 in words is "one hundred twenty-eight million, one hundred twenty-eight thousand, three hundred eighty-eight".