340805 has 4 divisors (see below), whose sum is σ = 408972. Its totient is φ = 272640.

The previous prime is 340801. The next prime is 340811. The reversal of 340805 is 508043.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 508043 = 83 ⋅6121.

It can be written as a sum of positive squares in 2 ways, for example, as 206116 + 134689 = 454^2 + 367^2 .

It is not a de Polignac number, because 340805 - 2² = 340801 is a prime.

It is a super-2 number, since 2×340805² = 232296096050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (340801) 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, 34076 + ... + 34085.

It is an arithmetic number, because the mean of its divisors is an integer number (102243).

2³⁴⁰⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

340805 is a deficient number, since it is larger than the sum of its proper divisors (68167).

340805 is an equidigital number, since it uses as much as digits as its factorization.

340805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68166.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 340805 is about 583.7850631868. The cubic root of 340805 is about 69.8503606151.

Adding to 340805 its reverse (508043), we get a palindrome (848848).

The spelling of 340805 in words is "three hundred forty thousand, eight hundred five".