505303021 has 2 divisors, whose sum is σ = 505303022. Its totient is φ = 505303020.

The previous prime is 505303003. The next prime is 505303061. The reversal of 505303021 is 120303505.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 360582121 + 144720900 = 18989^2 + 12030^2 .

It is a cyclic number.

It is not a de Polignac number, because 505303021 - 2²¹ = 503205869 is a prime.

It is a super-2 number, since 2×505303021² = 510662286063452882, which contains 22 as substring.

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 505303021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505303061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252651510 + 252651511.

It is an arithmetic number, because the mean of its divisors is an integer number (252651511).

Almost surely, 2^505303021 is an apocalyptic number.

It is an amenable number.

505303021 is a deficient number, since it is larger than the sum of its proper divisors (1).

505303021 is an equidigital number, since it uses as much as digits as its factorization.

505303021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 450, while the sum is 19.

The square root of 505303021 is about 22478.9461719183. The cubic root of 505303021 is about 796.4966708548.

Adding to 505303021 its reverse (120303505), we get a palindrome (625606526).

The spelling of 505303021 in words is "five hundred five million, three hundred three thousand, twenty-one".