518381 has 4 divisors (see below), whose sum is σ = 548892. Its totient is φ = 487872.

The previous prime is 518341. The next prime is 518387. The reversal of 518381 is 183815.

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 198025 + 320356 = 445^2 + 566^2 .

It is a cyclic number.

It is not a de Polignac number, because 518381 - 2¹⁴ = 501997 is a prime.

It is a super-2 number, since 2×518381² = 537437722322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 518381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (518387) 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 in 3 ways as a sum of consecutive naturals, for example, 15230 + ... + 15263.

It is an arithmetic number, because the mean of its divisors is an integer number (137223).

2⁵¹⁸³⁸¹ is an apocalyptic number.

It is an amenable number.

518381 is a deficient number, since it is larger than the sum of its proper divisors (30511).

518381 is a wasteful number, since it uses less digits than its factorization.

518381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30510.

The product of its digits is 960, while the sum is 26.

The square root of 518381 is about 719.9868054347. The cubic root of 518381 is about 80.3309725761.

The spelling of 518381 in words is "five hundred eighteen thousand, three hundred eighty-one".