518689 has 2 divisors, whose sum is σ = 518690. Its totient is φ = 518688.

The previous prime is 518657. The next prime is 518699. The reversal of 518689 is 986815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 518400 + 289 = 720^2 + 17^2 .

It is a cyclic number.

It is not a de Polignac number, because 518689 - 2⁵ = 518657 is a prime.

It is not a weakly prime, because it can be changed into another prime (518699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 259344 + 259345.

It is an arithmetic number, because the mean of its divisors is an integer number (259345).

2⁵¹⁸⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

518689 is a deficient number, since it is larger than the sum of its proper divisors (1).

518689 is an equidigital number, since it uses as much as digits as its factorization.

518689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 37.

The square root of 518689 is about 720.2006664812. The cubic root of 518689 is about 80.3468791782.

The spelling of 518689 in words is "five hundred eighteen thousand, six hundred eighty-nine".