342809 has 4 divisors (see below), whose sum is σ = 354660. Its totient is φ = 330960.

The previous prime is 342803. The next prime is 342821. The reversal of 342809 is 908243.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 908243 = 7 ⋅129749.

It can be written as a sum of positive squares in 2 ways, for example, as 107584 + 235225 = 328^2 + 485^2 .

It is a cyclic number.

It is not a de Polignac number, because 342809 - 2⁸ = 342553 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 342809.

It is not an unprimeable number, because it can be changed into a prime (342803) 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, 5882 + ... + 5939.

It is an arithmetic number, because the mean of its divisors is an integer number (88665).

2³⁴²⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

342809 is a deficient number, since it is larger than the sum of its proper divisors (11851).

342809 is a wasteful number, since it uses less digits than its factorization.

342809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11850.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 342809 is about 585.4989325353. The cubic root of 342809 is about 69.9870043902.

The spelling of 342809 in words is "three hundred forty-two thousand, eight hundred nine".