505565321 has 4 divisors (see below), whose sum is σ = 506312772. Its totient is φ = 504817872.

The previous prime is 505565311. The next prime is 505565351. The reversal of 505565321 is 123565505.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 493062025 + 12503296 = 22205^2 + 3536^2 .

It is a cyclic number.

It is not a de Polignac number, because 505565321 - 2¹⁴ = 505548937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (505565311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 372710 + ... + 374063.

It is an arithmetic number, because the mean of its divisors is an integer number (126578193).

Almost surely, 2^505565321 is an apocalyptic number.

It is an amenable number.

505565321 is a deficient number, since it is larger than the sum of its proper divisors (747451).

505565321 is an equidigital number, since it uses as much as digits as its factorization.

505565321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 747450.

The product of its (nonzero) digits is 22500, while the sum is 32.

The square root of 505565321 is about 22484.7797632087. The cubic root of 505565321 is about 796.6344660184.

The spelling of 505565321 in words is "five hundred five million, five hundred sixty-five thousand, three hundred twenty-one".