509931 has 6 divisors (see below), whose sum is σ = 736580. Its totient is φ = 339948.

The previous prime is 509921. The next prime is 509939. The reversal of 509931 is 139905.

It is not a de Polignac number, because 509931 - 2⁶ = 509867 is a prime.

It is a super-2 number, since 2×509931² = 520059249522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 509895 and 509904.

It is not an unprimeable number, because it can be changed into a prime (509939) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 28321 + ... + 28338.

2⁵⁰⁹⁹³¹ is an apocalyptic number.

509931 is a deficient number, since it is larger than the sum of its proper divisors (226649).

509931 is a wasteful number, since it uses less digits than its factorization.

509931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56665 (or 56662 counting only the distinct ones).

The product of its (nonzero) digits is 1215, while the sum is 27.

The square root of 509931 is about 714.0945315573. The cubic root of 509931 is about 79.8920941027.

The spelling of 509931 in words is "five hundred nine thousand, nine hundred thirty-one".