818506 has 8 divisors (see below), whose sum is σ = 1322244. Its totient is φ = 377760.

The previous prime is 818473. The next prime is 818509. The reversal of 818506 is 605818.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 654481 + 164025 = 809^2 + 405^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (818509) by changing a digit.

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, 15715 + ... + 15766.

2⁸¹⁸⁵⁰⁶ is an apocalyptic number.

818506 is a deficient number, since it is larger than the sum of its proper divisors (503738).

818506 is a wasteful number, since it uses less digits than its factorization.

818506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31496.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 818506 is about 904.7132142287. The cubic root of 818506 is about 93.5421373933.

The spelling of 818506 in words is "eight hundred eighteen thousand, five hundred six".