261728135 has 8 divisors (see below), whose sum is σ = 330604080. Its totient is φ = 198362304.

The previous prime is 261728119. The next prime is 261728231. The reversal of 261728135 is 531827162.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 261728135 - 2⁴ = 261728119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261728095 and 261728104.

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 7 ways as a sum of consecutive naturals, for example, 1377422 + ... + 1377611.

It is an arithmetic number, because the mean of its divisors is an integer number (41325510).

Almost surely, 2^261728135 is an apocalyptic number.

261728135 is a deficient number, since it is larger than the sum of its proper divisors (68875945).

261728135 is a wasteful number, since it uses less digits than its factorization.

261728135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2755057.

The product of its digits is 20160, while the sum is 35.

The square root of 261728135 is about 16178.0139386762. The cubic root of 261728135 is about 639.6613890761.

The spelling of 261728135 in words is "two hundred sixty-one million, seven hundred twenty-eight thousand, one hundred thirty-five".