505136809 has 2 divisors, whose sum is σ = 505136810. Its totient is φ = 505136808.

The previous prime is 505136789. The next prime is 505136843. The reversal of 505136809 is 908631505.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 352688400 + 152448409 = 18780^2 + 12347^2 .

It is a cyclic number.

It is not a de Polignac number, because 505136809 - 2¹¹ = 505134761 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (505136899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252568404 + 252568405.

It is an arithmetic number, because the mean of its divisors is an integer number (252568405).

Almost surely, 2^505136809 is an apocalyptic number.

It is an amenable number.

505136809 is a deficient number, since it is larger than the sum of its proper divisors (1).

505136809 is an equidigital number, since it uses as much as digits as its factorization.

505136809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 505136809 is about 22475.2488084114. The cubic root of 505136809 is about 796.4093293208.

The spelling of 505136809 in words is "five hundred five million, one hundred thirty-six thousand, eight hundred nine".