561505 has 16 divisors (see below), whose sum is σ = 785664. Its totient is φ = 377280.

The previous prime is 561461. The next prime is 561521. The reversal of 561505 is 505165.

It is not a de Polignac number, because 561505 - 2⁷ = 561377 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 15 ways as a sum of consecutive naturals, for example, 2004 + ... + 2266.

It is an arithmetic number, because the mean of its divisors is an integer number (49104).

2⁵⁶¹⁵⁰⁵ is an apocalyptic number.

It is an amenable number.

561505 is a deficient number, since it is larger than the sum of its proper divisors (224159).

561505 is a wasteful number, since it uses less digits than its factorization.

561505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336.

The product of its (nonzero) digits is 750, while the sum is 22.

The square root of 561505 is about 749.3363730662. The cubic root of 561505 is about 82.4994796417.

The spelling of 561505 in words is "five hundred sixty-one thousand, five hundred five".