128205125 has 8 divisors (see below), whose sum is σ = 160000152. Its totient is φ = 102564000.

The previous prime is 128205089. The next prime is 128205127. The reversal of 128205125 is 521502821.

It can be written as a sum of positive squares in 4 ways, for example, as 27363361 + 100841764 = 5231^2 + 10042^2 .

It is not a de Polignac number, because 128205125 - 2⁶ = 128205061 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 128205094 and 128205103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128205127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 512696 + ... + 512945.

It is an arithmetic number, because the mean of its divisors is an integer number (20000019).

Almost surely, 2^128205125 is an apocalyptic number.

It is an amenable number.

128205125 is a deficient number, since it is larger than the sum of its proper divisors (31795027).

128205125 is an equidigital number, since it uses as much as digits as its factorization.

128205125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1025656 (or 1025646 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 26.

The square root of 128205125 is about 11322.7701999113. The cubic root of 128205125 is about 504.2374859726.

Adding to 128205125 its reverse (521502821), we get a palindrome (649707946).

The spelling of 128205125 in words is "one hundred twenty-eight million, two hundred five thousand, one hundred twenty-five".