505161 has 18 divisors (see below), whose sum is σ = 768222. Its totient is φ = 319680.

The previous prime is 505159. The next prime is 505181. The reversal of 505161 is 161505.

505161 is a `hidden beast` number, since 505 + 161 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 145161 + 360000 = 381^2 + 600^2 .

It is not a de Polignac number, because 505161 - 2¹ = 505159 is a prime.

It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.

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 505161.

It is not an unprimeable number, because it can be changed into a prime (505111) 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 17 ways as a sum of consecutive naturals, for example, 12301 + ... + 12341.

It is an arithmetic number, because the mean of its divisors is an integer number (42679).

2⁵⁰⁵¹⁶¹ is an apocalyptic number.

It is an amenable number.

505161 is a deficient number, since it is larger than the sum of its proper divisors (263061).

505161 is a wasteful number, since it uses less digits than its factorization.

505161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 18.

The square root of 505161 is about 710.7467903550. The cubic root of 505161 is about 79.6422042465.

Adding to 505161 its reverse (161505), we get a palindrome (666666).

It can be divided in two parts, 505 and 161, that added together give a palindrome (666).

The spelling of 505161 in words is "five hundred five thousand, one hundred sixty-one".