509261 has 4 divisors (see below), whose sum is σ = 521724. Its totient is φ = 496800.

The previous prime is 509239. The next prime is 509263. The reversal of 509261 is 162905.

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

It can be written as a sum of positive squares in 2 ways, for example, as 265225 + 244036 = 515^2 + 494^2 .

It is a cyclic number.

It is not a de Polignac number, because 509261 - 2¹⁰ = 508237 is a prime.

It is a super-2 number, since 2×509261² = 518693532242, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (509263) 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, 6170 + ... + 6251.

It is an arithmetic number, because the mean of its divisors is an integer number (130431).

2⁵⁰⁹²⁶¹ is an apocalyptic number.

It is an amenable number.

509261 is a deficient number, since it is larger than the sum of its proper divisors (12463).

509261 is a wasteful number, since it uses less digits than its factorization.

509261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12462.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 509261 is about 713.6252517954. The cubic root of 509261 is about 79.8570886062.

The spelling of 509261 in words is "five hundred nine thousand, two hundred sixty-one".