561165 has 32 divisors (see below), whose sum is σ = 1036800. Its totient is φ = 256320.

The previous prime is 561161. The next prime is 561173.

561165 = T₃₃₀ + T₃₃₁ + ... + T₃₃₉.

561165 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 561165 - 2² = 561161 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561161) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3046 + ... + 3224.

It is an arithmetic number, because the mean of its divisors is an integer number (32400).

2⁵⁶¹¹⁶⁵ is an apocalyptic number.

561165 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

561165 is a deficient number, since it is larger than the sum of its proper divisors (475635).

561165 is a wasteful number, since it uses less digits than its factorization.

561165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217.

The product of its digits is 900, while the sum is 24.

The square root of 561165 is about 749.1094713058. The cubic root of 561165 is about 82.4828247074.

It can be divided in two parts, 56 and 1165, that added together give a palindrome (1221).

The spelling of 561165 in words is "five hundred sixty-one thousand, one hundred sixty-five".