128905578 has 12 divisors (see below), whose sum is σ = 279295458. Its totient is φ = 42968520.

The previous prime is 128905559. The next prime is 128905603. The reversal of 128905578 is 875509821.

It is a happy number.

128905578 is a `hidden beast` number, since 1 + 2 + 8 + 90 + 557 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 114639849 + 14265729 = 10707^2 + 3777^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3580693 + ... + 3580728.

Almost surely, 2^128905578 is an apocalyptic number.

128905578 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

128905578 is an abundant number, since it is smaller than the sum of its proper divisors (150389880).

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

128905578 is a wasteful number, since it uses less digits than its factorization.

128905578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7161429 (or 7161426 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 45.

The square root of 128905578 is about 11353.6592339210. The cubic root of 128905578 is about 505.1541247699.

The spelling of 128905578 in words is "one hundred twenty-eight million, nine hundred five thousand, five hundred seventy-eight".