170561 has 8 divisors (see below), whose sum is σ = 184320. Its totient is φ = 157248.

The previous prime is 170557. The next prime is 170579. The reversal of 170561 is 165071.

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 170561 - 2² = 170557 is a prime.

It is a Duffinian number.

170561 is a modest number, since divided by 561 gives 17 as remainder.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (170551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1280 + ... + 1406.

It is an arithmetic number, because the mean of its divisors is an integer number (23040).

2¹⁷⁰⁵⁶¹ is an apocalyptic number.

It is an amenable number.

170561 is a deficient number, since it is larger than the sum of its proper divisors (13759).

170561 is a wasteful number, since it uses less digits than its factorization.

170561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223.

The product of its (nonzero) digits is 210, while the sum is 20.

The square root of 170561 is about 412.9903146564. The cubic root of 170561 is about 55.4574519011.

The spelling of 170561 in words is "one hundred seventy thousand, five hundred sixty-one".