506581 has 4 divisors (see below), whose sum is σ = 508032. Its totient is φ = 505132.

The previous prime is 506573. The next prime is 506591. The reversal of 506581 is 185605.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 506581 - 2³ = 506573 is a prime.

It is a super-2 number, since 2×506581² = 513248619122, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (506501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 156 + ... + 1018.

It is an arithmetic number, because the mean of its divisors is an integer number (127008).

2⁵⁰⁶⁵⁸¹ is an apocalyptic number.

It is an amenable number.

506581 is a deficient number, since it is larger than the sum of its proper divisors (1451).

506581 is an equidigital number, since it uses as much as digits as its factorization.

506581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1450.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 506581 is about 711.7450386199. The cubic root of 506581 is about 79.7167587803.

The spelling of 506581 in words is "five hundred six thousand, five hundred eighty-one".