505009 has 4 divisors (see below), whose sum is σ = 510016. Its totient is φ = 500004.

The previous prime is 504991. The next prime is 505027. The reversal of 505009 is 900505.

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 an interprime number because it is at equal distance from previous prime (504991) and next prime (505027).

It is a cyclic number.

It is not a de Polignac number, because 505009 - 2¹¹ = 502961 is a prime.

It is a Duffinian number.

505009 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2349 + ... + 2554.

It is an arithmetic number, because the mean of its divisors is an integer number (127504).

2⁵⁰⁵⁰⁰⁹ is an apocalyptic number.

It is an amenable number.

505009 is a deficient number, since it is larger than the sum of its proper divisors (5007).

505009 is a wasteful number, since it uses less digits than its factorization.

505009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5006.

The product of its (nonzero) digits is 225, while the sum is 19.

The square root of 505009 is about 710.6398525273. The cubic root of 505009 is about 79.6342154868.

The spelling of 505009 in words is "five hundred five thousand, nine".