505800509 has 2 divisors, whose sum is σ = 505800510. Its totient is φ = 505800508.

The previous prime is 505800499. The next prime is 505800551. The reversal of 505800509 is 905008505.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 336722500 + 169078009 = 18350^2 + 13003^2 .

It is a cyclic number.

It is not a de Polignac number, because 505800509 - 2¹² = 505796413 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505800599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252900254 + 252900255.

It is an arithmetic number, because the mean of its divisors is an integer number (252900255).

Almost surely, 2^505800509 is an apocalyptic number.

It is an amenable number.

505800509 is a deficient number, since it is larger than the sum of its proper divisors (1).

505800509 is an equidigital number, since it uses as much as digits as its factorization.

505800509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9000, while the sum is 32.

The square root of 505800509 is about 22490.0090929284. The cubic root of 505800509 is about 796.7579778005.

The spelling of 505800509 in words is "five hundred five million, eight hundred thousand, five hundred nine".