128272685 has 8 divisors (see below), whose sum is σ = 154317336. Its totient is φ = 102358080.

The previous prime is 128272681. The next prime is 128272717. The reversal of 128272685 is 586272821.

It can be written as a sum of positive squares in 4 ways, for example, as 605284 + 127667401 = 778^2 + 11299^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 128272685 - 2² = 128272681 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128272681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30326 + ... + 34295.

It is an arithmetic number, because the mean of its divisors is an integer number (19289667).

Almost surely, 2^128272685 is an apocalyptic number.

It is an amenable number.

128272685 is a deficient number, since it is larger than the sum of its proper divisors (26044651).

128272685 is an equidigital number, since it uses as much as digits as its factorization.

128272685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65023.

The product of its digits is 107520, while the sum is 41.

The square root of 128272685 is about 11325.7531758378. The cubic root of 128272685 is about 504.3260427609.

The spelling of 128272685 in words is "one hundred twenty-eight million, two hundred seventy-two thousand, six hundred eighty-five".