518440 has 32 divisors (see below), whose sum is σ = 1257480. Its totient is φ = 191232.

The previous prime is 518431. The next prime is 518447. The reversal of 518440 is 44815.

It can be written as a sum of positive squares in 4 ways, for example, as 417316 + 101124 = 646^2 + 318^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (518447) by changing a digit.

518440 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22 + ... + 1018.

2⁵¹⁸⁴⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 518440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (628740).

518440 is an abundant number, since it is smaller than the sum of its proper divisors (739040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

518440 is a wasteful number, since it uses less digits than its factorization.

518440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1021 (or 1017 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 518440 is about 720.0277772420. The cubic root of 518440 is about 80.3340201078.

The spelling of 518440 in words is "five hundred eighteen thousand, four hundred forty".