505819 has 2 divisors, whose sum is σ = 505820. Its totient is φ = 505818.

The previous prime is 505811. The next prime is 505823. The reversal of 505819 is 918505.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 505819 - 2³ = 505811 is a prime.

It is a super-2 number, since 2×505819² = 511705721522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (505811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252909 + 252910.

It is an arithmetic number, because the mean of its divisors is an integer number (252910).

2⁵⁰⁵⁸¹⁹ is an apocalyptic number.

505819 is a deficient number, since it is larger than the sum of its proper divisors (1).

505819 is an equidigital number, since it uses as much as digits as its factorization.

505819 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 28.

The square root of 505819 is about 711.2095331195. The cubic root of 505819 is about 79.6767686946.

Subtracting 505819 from its reverse (918505), we obtain a triangular number (412686 = T₉₀₈).

It can be divided in two parts, 505 and 819, that multiplied together give a triangular number (413595 = T₉₀₉).

The spelling of 505819 in words is "five hundred five thousand, eight hundred nineteen".