128397555 has 96 divisors (see below), whose sum is σ = 271514880. Its totient is φ = 57386880.

The previous prime is 128397553. The next prime is 128397557. The reversal of 128397555 is 555793821.

128397555 is a `hidden beast` number, since 1 + 2 + 8 + 3 + 97 + 555 = 666.

It is an interprime number because it is at equal distance from previous prime (128397553) and next prime (128397557).

It is not a de Polignac number, because 128397555 - 2¹ = 128397553 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 128397555.

It is not an unprimeable number, because it can be changed into a prime (128397551) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 173376 + ... + 174114.

It is an arithmetic number, because the mean of its divisors is an integer number (2828280).

Almost surely, 2^128397555 is an apocalyptic number.

128397555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128397555 is an abundant number, since it is smaller than the sum of its proper divisors (143117325).

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

128397555 is a wasteful number, since it uses less digits than its factorization.

128397555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 783 (or 771 counting only the distinct ones).

The product of its digits is 378000, while the sum is 45.

The square root of 128397555 is about 11331.2644925445. The cubic root of 128397555 is about 504.4896389548.

The spelling of 128397555 in words is "one hundred twenty-eight million, three hundred ninety-seven thousand, five hundred fifty-five".