128275209 has 12 divisors (see below), whose sum is σ = 193342656. Its totient is φ = 81798552.

The previous prime is 128275187. The next prime is 128275219. The reversal of 128275209 is 902572821.

128275209 is a `hidden beast` number, since 128 + 2 + 7 + 520 + 9 = 666.

It is not a de Polignac number, because 128275209 - 2¹⁶ = 128209673 is a prime.

It is a super-3 number, since 3×128275209³ (a number of 25 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (128275219) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 309637 + ... + 310050.

It is an arithmetic number, because the mean of its divisors is an integer number (16111888).

Almost surely, 2^128275209 is an apocalyptic number.

It is an amenable number.

128275209 is a deficient number, since it is larger than the sum of its proper divisors (65067447).

128275209 is a wasteful number, since it uses less digits than its factorization.

128275209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619716 (or 619713 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 128275209 is about 11325.8646027577. The cubic root of 128275209 is about 504.3293505854.

The spelling of 128275209 in words is "one hundred twenty-eight million, two hundred seventy-five thousand, two hundred nine".