561265 has 4 divisors (see below), whose sum is σ = 673524. Its totient is φ = 449008.

The previous prime is 561251. The next prime is 561277. The reversal of 561265 is 562165.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 136161 + 425104 = 369^2 + 652^2 .

It is a cyclic number.

It is not a de Polignac number, because 561265 - 2⁹ = 560753 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 56122 + ... + 56131.

It is an arithmetic number, because the mean of its divisors is an integer number (168381).

2⁵⁶¹²⁶⁵ is an apocalyptic number.

It is an amenable number.

561265 is a deficient number, since it is larger than the sum of its proper divisors (112259).

561265 is a wasteful number, since it uses less digits than its factorization.

561265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112258.

The product of its digits is 1800, while the sum is 25.

The square root of 561265 is about 749.1762142514. The cubic root of 561265 is about 82.4877239157.

Subtracting 561265 from its reverse (562165), we obtain a square (900 = 30²).

The spelling of 561265 in words is "five hundred sixty-one thousand, two hundred sixty-five".