818309 has 2 divisors, whose sum is σ = 818310. Its totient is φ = 818308.

The previous prime is 818303. The next prime is 818327. The reversal of 818309 is 903818.

It is a happy number.

818309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 521284 + 297025 = 722^2 + 545^2 .

It is a cyclic number.

It is not a de Polignac number, because 818309 - 2¹² = 814213 is a prime.

It is a Sophie Germain prime.

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a plaindrome in base 15.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (818303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 409154 + 409155.

It is an arithmetic number, because the mean of its divisors is an integer number (409155).

2⁸¹⁸³⁰⁹ is an apocalyptic number.

It is an amenable number.

818309 is a deficient number, since it is larger than the sum of its proper divisors (1).

818309 is an equidigital number, since it uses as much as digits as its factorization.

818309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 818309 is about 904.6043333967. The cubic root of 818309 is about 93.5346321420.

The spelling of 818309 in words is "eight hundred eighteen thousand, three hundred nine".