509486809 has 4 divisors (see below), whose sum is σ = 548678116. Its totient is φ = 470295504.

The previous prime is 509486797. The next prime is 509486839. The reversal of 509486809 is 908684905.

It is a happy number.

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 274631184 + 234855625 = 16572^2 + 15325^2 .

It is a cyclic number.

It is not a de Polignac number, because 509486809 - 2¹¹ = 509484761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (509486839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19595634 + ... + 19595659.

It is an arithmetic number, because the mean of its divisors is an integer number (137169529).

Almost surely, 2^509486809 is an apocalyptic number.

It is an amenable number.

509486809 is a deficient number, since it is larger than the sum of its proper divisors (39191307).

509486809 is a wasteful number, since it uses less digits than its factorization.

509486809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39191306.

The product of its (nonzero) digits is 622080, while the sum is 49.

The square root of 509486809 is about 22571.8144817824. The cubic root of 509486809 is about 798.6888987950.

The spelling of 509486809 in words is "five hundred nine million, four hundred eighty-six thousand, eight hundred nine".