561561541 has 4 divisors (see below), whose sum is σ = 562254784. Its totient is φ = 560868300.

The previous prime is 561561509. The next prime is 561561599. The reversal of 561561541 is 145165165.

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.

It is a cyclic number.

It is not a de Polignac number, because 561561541 - 2⁵ = 561561509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 561561497 and 561561506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561561841) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 345405 + ... + 347026.

It is an arithmetic number, because the mean of its divisors is an integer number (140563696).

Almost surely, 2^561561541 is an apocalyptic number.

It is an amenable number.

561561541 is a deficient number, since it is larger than the sum of its proper divisors (693243).

561561541 is an equidigital number, since it uses as much as digits as its factorization.

561561541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693242.

The product of its digits is 18000, while the sum is 34.

The square root of 561561541 is about 23697.2897395462. The cubic root of 561561541 is about 825.0224865619.

The spelling of 561561541 in words is "five hundred sixty-one million, five hundred sixty-one thousand, five hundred forty-one".