505513220521 has 2 divisors, whose sum is σ = 505513220522. Its totient is φ = 505513220520.

The previous prime is 505513220497. The next prime is 505513220581. The reversal of 505513220521 is 125022315505.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 495983556121 + 9529664400 = 704261^2 + 97620^2 .

It is a cyclic number.

It is not a de Polignac number, because 505513220521 - 2¹⁷ = 505513089449 is a prime.

It is a super-2 number, since 2×505513220521² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (505513220581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252756610260 + 252756610261.

It is an arithmetic number, because the mean of its divisors is an integer number (252756610261).

Almost surely, 2^505513220521 is an apocalyptic number.

It is an amenable number.

505513220521 is a deficient number, since it is larger than the sum of its proper divisors (1).

505513220521 is an equidigital number, since it uses as much as digits as its factorization.

505513220521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15000, while the sum is 31.

The spelling of 505513220521 in words is "five hundred five billion, five hundred thirteen million, two hundred twenty thousand, five hundred twenty-one".