320009509 has 4 divisors (see below), whose sum is σ = 320049216. Its totient is φ = 319969804.

The previous prime is 320009491. The next prime is 320009549. The reversal of 320009509 is 905900023.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 320009509 - 2¹¹ = 320007461 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 (320009549) 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, 2989 + ... + 25474.

It is an arithmetic number, because the mean of its divisors is an integer number (80012304).

Almost surely, 2^320009509 is an apocalyptic number.

It is an amenable number.

320009509 is a deficient number, since it is larger than the sum of its proper divisors (39707).

320009509 is a wasteful number, since it uses less digits than its factorization.

320009509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39706.

The product of its (nonzero) digits is 2430, while the sum is 28.

The square root of 320009509 is about 17888.8096026538. The cubic root of 320009509 is about 683.9971536708.

The spelling of 320009509 in words is "three hundred twenty million, nine thousand, five hundred nine".