506405 has 4 divisors (see below), whose sum is σ = 607692. Its totient is φ = 405120.

The previous prime is 506393. The next prime is 506417. The reversal of 506405 is 504605.

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 (506393) and next prime (506417).

It can be written as a sum of positive squares in 2 ways, for example, as 73441 + 432964 = 271^2 + 658^2 .

It is not a de Polignac number, because 506405 - 2¹⁸ = 244261 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 506405.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50636 + ... + 50645.

It is an arithmetic number, because the mean of its divisors is an integer number (151923).

2⁵⁰⁶⁴⁰⁵ is an apocalyptic number.

It is an amenable number.

506405 is a deficient number, since it is larger than the sum of its proper divisors (101287).

506405 is a wasteful number, since it uses less digits than its factorization.

506405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101286.

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 506405 is about 711.6213880990. The cubic root of 506405 is about 79.7075257885.

The spelling of 506405 in words is "five hundred six thousand, four hundred five".