509311 has 4 divisors (see below), whose sum is σ = 555624. Its totient is φ = 463000.

The previous prime is 509297. The next prime is 509317. The reversal of 509311 is 113905.

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

It is a cyclic number.

It is not a de Polignac number, because 509311 - 2⁹ = 508799 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (509317) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23140 + ... + 23161.

It is an arithmetic number, because the mean of its divisors is an integer number (138906).

2⁵⁰⁹³¹¹ is an apocalyptic number.

509311 is a deficient number, since it is larger than the sum of its proper divisors (46313).

509311 is a wasteful number, since it uses less digits than its factorization.

509311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46312.

The product of its (nonzero) digits is 135, while the sum is 19.

The square root of 509311 is about 713.6602833281. The cubic root of 509311 is about 79.8597020164.

It can be divided in two parts, 509 and 311, that added together give a triangular number (820 = T₄₀).

The spelling of 509311 in words is "five hundred nine thousand, three hundred eleven".