505309 has 8 divisors (see below), whose sum is σ = 593408. Its totient is φ = 421200.

The previous prime is 505301. The next prime is 505313. The reversal of 505309 is 903505.

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 505309 - 2³ = 505301 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 505309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505301) 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, 717 + ... + 1234.

It is an arithmetic number, because the mean of its divisors is an integer number (74176).

2⁵⁰⁵³⁰⁹ is an apocalyptic number.

It is an amenable number.

505309 is a deficient number, since it is larger than the sum of its proper divisors (88099).

505309 is a wasteful number, since it uses less digits than its factorization.

505309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1995.

The product of its (nonzero) digits is 675, while the sum is 22.

The square root of 505309 is about 710.8508985716. The cubic root of 505309 is about 79.6499812359.

The spelling of 505309 in words is "five hundred five thousand, three hundred nine".