505591 has 4 divisors (see below), whose sum is σ = 512784. Its totient is φ = 498400.

The previous prime is 505573. The next prime is 505601. The reversal of 505591 is 195505.

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

It is a cyclic number.

It is not a de Polignac number, because 505591 - 2⁵ = 505559 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505501) 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, 3490 + ... + 3631.

It is an arithmetic number, because the mean of its divisors is an integer number (128196).

2⁵⁰⁵⁵⁹¹ is an apocalyptic number.

505591 is a deficient number, since it is larger than the sum of its proper divisors (7193).

505591 is an equidigital number, since it uses as much as digits as its factorization.

505591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7192.

The product of its (nonzero) digits is 1125, while the sum is 25.

The square root of 505591 is about 711.0492247376. The cubic root of 505591 is about 79.6647953514.

The spelling of 505591 in words is "five hundred five thousand, five hundred ninety-one".