521245717 has 2 divisors, whose sum is σ = 521245718. Its totient is φ = 521245716.

The previous prime is 521245709. The next prime is 521245723. The reversal of 521245717 is 717542125.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 518290756 + 2954961 = 22766^2 + 1719^2 .

It is a cyclic number.

It is not a de Polignac number, because 521245717 - 2³ = 521245709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521245787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260622858 + 260622859.

It is an arithmetic number, because the mean of its divisors is an integer number (260622859).

Almost surely, 2^521245717 is an apocalyptic number.

It is an amenable number.

521245717 is a deficient number, since it is larger than the sum of its proper divisors (1).

521245717 is an equidigital number, since it uses as much as digits as its factorization.

521245717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19600, while the sum is 34.

The square root of 521245717 is about 22830.8063151523. The cubic root of 521245717 is about 804.7867789134.

The spelling of 521245717 in words is "five hundred twenty-one million, two hundred forty-five thousand, seven hundred seventeen".