505803689 has 2 divisors, whose sum is σ = 505803690. Its totient is φ = 505803688.

The previous prime is 505803677. The next prime is 505803691. The reversal of 505803689 is 986308505.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 450925225 + 54878464 = 21235^2 + 7408^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-505803689 is a prime.

Together with 505803691, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (505803889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252901844 + 252901845.

It is an arithmetic number, because the mean of its divisors is an integer number (252901845).

Almost surely, 2^505803689 is an apocalyptic number.

It is an amenable number.

505803689 is a deficient number, since it is larger than the sum of its proper divisors (1).

505803689 is an equidigital number, since it uses as much as digits as its factorization.

505803689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 259200, while the sum is 44.

The square root of 505803689 is about 22490.0797908767. The cubic root of 505803689 is about 796.7596475530.

The spelling of 505803689 in words is "five hundred five million, eight hundred three thousand, six hundred eighty-nine".