517320217 has 4 divisors (see below), whose sum is σ = 547750836. Its totient is φ = 486889600.

The previous prime is 517320197. The next prime is 517320259. The reversal of 517320217 is 712023715.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 481188096 + 36132121 = 21936^2 + 6011^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-517320217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (517320017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15215284 + ... + 15215317.

It is an arithmetic number, because the mean of its divisors is an integer number (136937709).

Almost surely, 2^517320217 is an apocalyptic number.

It is an amenable number.

517320217 is a deficient number, since it is larger than the sum of its proper divisors (30430619).

517320217 is a wasteful number, since it uses less digits than its factorization.

517320217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30430618.

The product of its (nonzero) digits is 2940, while the sum is 28.

The square root of 517320217 is about 22744.6744755778. The cubic root of 517320217 is about 802.7614036992.

The spelling of 517320217 in words is "five hundred seventeen million, three hundred twenty thousand, two hundred seventeen".