561530809 has 8 divisors (see below), whose sum is σ = 669651840. Its totient is φ = 460385376.

The previous prime is 561530779. The next prime is 561530821. The reversal of 561530809 is 908035165.

561530809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 561530809 - 2⁹ = 561530297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561531809) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1743724 + ... + 1744045.

It is an arithmetic number, because the mean of its divisors is an integer number (83706480).

Almost surely, 2^561530809 is an apocalyptic number.

It is an amenable number.

561530809 is a deficient number, since it is larger than the sum of its proper divisors (108121031).

561530809 is a wasteful number, since it uses less digits than its factorization.

561530809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3487799.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 561530809 is about 23696.6413020917. The cubic root of 561530809 is about 825.0074362354.

The spelling of 561530809 in words is "five hundred sixty-one million, five hundred thirty thousand, eight hundred nine".