505818 has 64 divisors (see below), whose sum is σ = 1296000. Its totient is φ = 145152.

The previous prime is 505811. The next prime is 505819. The reversal of 505818 is 818505.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 505791 and 505800.

It is not an unprimeable number, because it can be changed into a prime (505811) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17428 + ... + 17456.

It is an arithmetic number, because the mean of its divisors is an integer number (20250).

2⁵⁰⁵⁸¹⁸ is an apocalyptic number.

505818 is a gapful number since it is divisible by the number (58) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 505818, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (648000).

505818 is an abundant number, since it is smaller than the sum of its proper divisors (790182).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

505818 is a wasteful number, since it uses less digits than its factorization.

505818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76 (or 70 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 27.

The square root of 505818 is about 711.2088300914. The cubic root of 505818 is about 79.6767161878.

The spelling of 505818 in words is "five hundred five thousand, eight hundred eighteen".