128138400 has 324 divisors, whose sum is σ = 500112522. Its totient is φ = 30689280.

The previous prime is 128138399. The next prime is 128138441. The reversal of 128138400 is 4831821.

128138400 is a `hidden beast` number, since 1 + 281 + 384 + 0 + 0 = 666.

It can be written as a sum of positive squares in 9 ways, for example, as 30603024 + 97535376 = 5532^2 + 9876^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 3463182 + ... + 3463218.

Almost surely, 2^128138400 is an apocalyptic number.

128138400 is a gapful number since it is divisible by the number (10) 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 128138400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (250056261).

128138400 is an abundant number, since it is smaller than the sum of its proper divisors (371974122).

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

128138400 is a wasteful number, since it uses less digits than its factorization.

128138400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 128138400 is about 11319.8233201760. The cubic root of 128138400 is about 504.1499931497.

The spelling of 128138400 in words is "one hundred twenty-eight million, one hundred thirty-eight thousand, four hundred".