409309 has 4 divisors (see below), whose sum is σ = 433404. Its totient is φ = 385216.

The previous prime is 409291. The next prime is 409327. The reversal of 409309 is 903904.

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

It is an interprime number because it is at equal distance from previous prime (409291) and next prime (409327).

It can be written as a sum of positive squares in 2 ways, for example, as 356409 + 52900 = 597^2 + 230^2 .

It is a cyclic number.

It is not a de Polignac number, because 409309 - 2¹⁷ = 278237 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 (409349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12022 + ... + 12055.

It is an arithmetic number, because the mean of its divisors is an integer number (108351).

2⁴⁰⁹³⁰⁹ is an apocalyptic number.

It is an amenable number.

409309 is a deficient number, since it is larger than the sum of its proper divisors (24095).

409309 is a wasteful number, since it uses less digits than its factorization.

409309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24094.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 409309 is about 639.7726158566. The cubic root of 409309 is about 74.2478299010.

The spelling of 409309 in words is "four hundred nine thousand, three hundred nine".