505523209 has 2 divisors, whose sum is σ = 505523210. Its totient is φ = 505523208.

The previous prime is 505523171. The next prime is 505523219. The reversal of 505523209 is 902325505.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 492706809 + 12816400 = 22197^2 + 3580^2 .

It is a cyclic number.

It is not a de Polignac number, because 505523209 - 2⁹ = 505522697 is a prime.

It is not a weakly prime, because it can be changed into another prime (505523219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252761604 + 252761605.

It is an arithmetic number, because the mean of its divisors is an integer number (252761605).

Almost surely, 2^505523209 is an apocalyptic number.

It is an amenable number.

505523209 is a deficient number, since it is larger than the sum of its proper divisors (1).

505523209 is an equidigital number, since it uses as much as digits as its factorization.

505523209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13500, while the sum is 31.

The square root of 505523209 is about 22483.8432880146. The cubic root of 505523209 is about 796.6123463563.

The spelling of 505523209 in words is "five hundred five million, five hundred twenty-three thousand, two hundred nine".