520421717 has 2 divisors, whose sum is σ = 520421718. Its totient is φ = 520421716.

The previous prime is 520421653. The next prime is 520421749. The reversal of 520421717 is 717124025.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 423083761 + 97337956 = 20569^2 + 9866^2 .

It is a cyclic number.

It is not a de Polignac number, because 520421717 - 2⁶ = 520421653 is a prime.

It is a super-4 number, since 4×520421717⁴ (a number of 36 digits) contains 4444 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 520421717.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (520421767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260210858 + 260210859.

It is an arithmetic number, because the mean of its divisors is an integer number (260210859).

Almost surely, 2^520421717 is an apocalyptic number.

It is an amenable number.

520421717 is a deficient number, since it is larger than the sum of its proper divisors (1).

520421717 is an equidigital number, since it uses as much as digits as its factorization.

520421717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3920, while the sum is 29.

The square root of 520421717 is about 22812.7533848942. The cubic root of 520421717 is about 804.3624786710.

The spelling of 520421717 in words is "five hundred twenty million, four hundred twenty-one thousand, seven hundred seventeen".