128820125 has 64 divisors (see below), whose sum is σ = 198042624. Its totient is φ = 81734400.

The previous prime is 128820119. The next prime is 128820149. The reversal of 128820125 is 521028821.

It is a happy number.

It is not a de Polignac number, because 128820125 - 2¹⁸ = 128557981 is a prime.

It is a Duffinian number.

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 744539 + ... + 744711.

It is an arithmetic number, because the mean of its divisors is an integer number (3094416).

Almost surely, 2^128820125 is an apocalyptic number.

It is an amenable number.

128820125 is a deficient number, since it is larger than the sum of its proper divisors (69222499).

128820125 is a wasteful number, since it uses less digits than its factorization.

128820125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255 (or 245 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 29.

The square root of 128820125 is about 11349.8953739671. The cubic root of 128820125 is about 505.0424759227.

Adding to 128820125 its reverse (521028821), we get a palindrome (649848946).

The spelling of 128820125 in words is "one hundred twenty-eight million, eight hundred twenty thousand, one hundred twenty-five".