505921765 has 4 divisors (see below), whose sum is σ = 607106124. Its totient is φ = 404737408.

The previous prime is 505921763. The next prime is 505921781. The reversal of 505921765 is 567129505.

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 209496676 + 296425089 = 14474^2 + 17217^2 .

It is a cyclic number.

It is not a de Polignac number, because 505921765 - 2¹ = 505921763 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505921763) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50592172 + ... + 50592181.

It is an arithmetic number, because the mean of its divisors is an integer number (151776531).

Almost surely, 2^505921765 is an apocalyptic number.

It is an amenable number.

505921765 is a deficient number, since it is larger than the sum of its proper divisors (101184359).

505921765 is a wasteful number, since it uses less digits than its factorization.

505921765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101184358.

The product of its (nonzero) digits is 94500, while the sum is 40.

The square root of 505921765 is about 22492.7047061931. The cubic root of 505921765 is about 796.8216418764.

The spelling of 505921765 in words is "five hundred five million, nine hundred twenty-one thousand, seven hundred sixty-five".