505921 has 4 divisors (see below), whose sum is σ = 544852. Its totient is φ = 466992.

The previous prime is 505919. The next prime is 505927. The reversal of 505921 is 129505.

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 65025 + 440896 = 255^2 + 664^2 .

It is a cyclic number.

It is not a de Polignac number, because 505921 - 2¹ = 505919 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 505892 and 505901.

It is not an unprimeable number, because it can be changed into a prime (505927) 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, 19446 + ... + 19471.

It is an arithmetic number, because the mean of its divisors is an integer number (136213).

2⁵⁰⁵⁹²¹ is an apocalyptic number.

It is an amenable number.

505921 is a deficient number, since it is larger than the sum of its proper divisors (38931).

505921 is a wasteful number, since it uses less digits than its factorization.

505921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38930.

The product of its (nonzero) digits is 450, while the sum is 22.

The square root of 505921 is about 711.2812383298. The cubic root of 505921 is about 79.6821240254.

The spelling of 505921 in words is "five hundred five thousand, nine hundred twenty-one".