394309 has 4 divisors (see below), whose sum is σ = 405004. Its totient is φ = 383616.

The previous prime is 394291. The next prime is 394319. The reversal of 394309 is 903493.

394309 = T₆₄ + T₆₅ + ... + T₁₃₇.

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 178084 + 216225 = 422^2 + 465^2 .

It is not a de Polignac number, because 394309 - 2⁹ = 393797 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 (394319) 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, 5292 + ... + 5365.

It is an arithmetic number, because the mean of its divisors is an integer number (101251).

2³⁹⁴³⁰⁹ is an apocalyptic number.

It is an amenable number.

394309 is a deficient number, since it is larger than the sum of its proper divisors (10695).

394309 is a wasteful number, since it uses less digits than its factorization.

394309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10694.

The product of its (nonzero) digits is 2916, while the sum is 28.

The square root of 394309 is about 627.9402837850. The cubic root of 394309 is about 73.3295291874.

It can be divided in two parts, 394 and 309, that added together give a triangular number (703 = T₃₇).

The spelling of 394309 in words is "three hundred ninety-four thousand, three hundred nine".