128520378 has 64 divisors (see below), whose sum is σ = 334033920. Its totient is φ = 35861616.

The previous prime is 128520367. The next prime is 128520383. The reversal of 128520378 is 873025821.

128520378 is a `hidden beast` number, since 1 + 285 + 2 + 0 + 378 = 666.

It is a super-2 number, since 2×128520378² = 33034975122525768, which contains 22 as substring.

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 31 ways as a sum of consecutive naturals, for example, 12301 + ... + 20207.

It is an arithmetic number, because the mean of its divisors is an integer number (5219280).

Almost surely, 2^128520378 is an apocalyptic number.

128520378 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 128520378, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (167016960).

128520378 is an abundant number, since it is smaller than the sum of its proper divisors (205513542).

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

128520378 is a wasteful number, since it uses less digits than its factorization.

128520378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7968 (or 7962 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 128520378 is about 11336.6828481704. The cubic root of 128520378 is about 504.6504498670.

The spelling of 128520378 in words is "one hundred twenty-eight million, five hundred twenty thousand, three hundred seventy-eight".