505665169 has 9 divisors (see below), whose sum is σ = 512756283. Its totient is φ = 498671712.

The previous prime is 505665091. The next prime is 505665217. The reversal of 505665169 is 961566505.

The square root of 505665169 is 22487.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 8910225 + 496754944 = 2985^2 + 22288^2 .

It is not a de Polignac number, because 505665169 - 2⁹ = 505664657 is a prime.

It is a super-2 number, since 2×505665169² = 511394526279597122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (505665269) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2540932 + ... + 2541130.

Almost surely, 2^505665169 is an apocalyptic number.

505665169 is the 22487-th square number.

505665169 is the 11244-th centered octagonal number.

It is an amenable number.

505665169 is a deficient number, since it is larger than the sum of its proper divisors (7091114).

505665169 is an frugal number, since it uses more digits than its factorization.

505665169 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624 (or 312 counting only the distinct ones).

The product of its (nonzero) digits is 243000, while the sum is 43.

The cubic root of 505665169 is about 796.6869070640.

It can be divided in two parts, 5056 and 65169, that added together give a square (70225 = 265²).

The spelling of 505665169 in words is "five hundred five million, six hundred sixty-five thousand, one hundred sixty-nine".