561841 has 4 divisors (see below), whose sum is σ = 642112. Its totient is φ = 481572.

The previous prime is 561839. The next prime is 561907. The reversal of 561841 is 148165.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 148165 = 5 ⋅29633.

It is not a de Polignac number, because 561841 - 2¹ = 561839 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (562841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40125 + ... + 40138.

It is an arithmetic number, because the mean of its divisors is an integer number (160528).

2⁵⁶¹⁸⁴¹ is an apocalyptic number.

It is an amenable number.

561841 is a deficient number, since it is larger than the sum of its proper divisors (80271).

561841 is an equidigital number, since it uses as much as digits as its factorization.

561841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80270.

The product of its digits is 960, while the sum is 25.

The square root of 561841 is about 749.5605379154. The cubic root of 561841 is about 82.5159320317.

The spelling of 561841 in words is "five hundred sixty-one thousand, eight hundred forty-one".