500921 has 2 divisors, whose sum is σ = 500922. Its totient is φ = 500920.

The previous prime is 500911. The next prime is 500923. The reversal of 500921 is 129005.

500921 is nontrivially palindromic in base 8.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 440896 + 60025 = 664^2 + 245^2 .

It is a cyclic number.

It is not a de Polignac number, because 500921 - 2¹⁰ = 499897 is a prime.

Together with 500923, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 500921.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 500921.

It is not a weakly prime, because it can be changed into another prime (500923) 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 as a sum of consecutive naturals, namely, 250460 + 250461.

It is an arithmetic number, because the mean of its divisors is an integer number (250461).

2⁵⁰⁰⁹²¹ is an apocalyptic number.

It is an amenable number.

500921 is a deficient number, since it is larger than the sum of its proper divisors (1).

500921 is an equidigital number, since it uses as much as digits as its factorization.

500921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90, while the sum is 17.

The square root of 500921 is about 707.7577269094. The cubic root of 500921 is about 79.4187559191.

Adding to 500921 its reverse (129005), we get a palindrome (629926).

The spelling of 500921 in words is "five hundred thousand, nine hundred twenty-one".