505418 has 4 divisors (see below), whose sum is σ = 758130. Its totient is φ = 252708.

The previous prime is 505411. The next prime is 505429. The reversal of 505418 is 814505.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 814505 = 5 ⋅162901.

It can be written as a sum of positive squares in only one way, i.e., 458329 + 47089 = 677^2 + 217^2 .

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 = 505393 and 505402.

It is not an unprimeable number, because it can be changed into a prime (505411) by changing a digit.

505418 is an untouchable number, because it is not equal to the sum of proper divisors of any 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 as a sum of consecutive naturals, namely, 126353 + ... + 126356.

2⁵⁰⁵⁴¹⁸ is an apocalyptic number.

505418 is a deficient number, since it is larger than the sum of its proper divisors (252712).

505418 is a wasteful number, since it uses less digits than its factorization.

505418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252711.

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 505418 is about 710.9275631174. The cubic root of 505418 is about 79.6557079126.

The spelling of 505418 in words is "five hundred five thousand, four hundred eighteen".