509331 has 4 divisors (see below), whose sum is σ = 679112. Its totient is φ = 339552.

The previous prime is 509329. The next prime is 509359. The reversal of 509331 is 133905.

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

It is not a de Polignac number, because 509331 - 2¹ = 509329 is a prime.

It is a super-2 number, since 2×509331² = 518836135122, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 509298 and 509307.

It is not an unprimeable number, because it can be changed into a prime (509731) 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, 84886 + ... + 84891.

It is an arithmetic number, because the mean of its divisors is an integer number (169778).

2⁵⁰⁹³³¹ is an apocalyptic number.

509331 is a deficient number, since it is larger than the sum of its proper divisors (169781).

509331 is a wasteful number, since it uses less digits than its factorization.

509331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169780.

The product of its (nonzero) digits is 405, while the sum is 21.

The square root of 509331 is about 713.6742954598. The cubic root of 509331 is about 79.8607473327.

The spelling of 509331 in words is "five hundred nine thousand, three hundred thirty-one".