523840 has 28 divisors (see below), whose sum is σ = 1248156. Its totient is φ = 209408.

The previous prime is 523829. The next prime is 523847. The reversal of 523840 is 48325.

It can be written as a sum of positive squares in 2 ways, for example, as 82944 + 440896 = 288^2 + 664^2 .

It is not an unprimeable number, because it can be changed into a prime (523847) by changing a digit.

523840 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 499 + ... + 1138.

It is an arithmetic number, because the mean of its divisors is an integer number (44577).

2⁵²³⁸⁴⁰ is an apocalyptic number.

It is an amenable number.

523840 is an abundant number, since it is smaller than the sum of its proper divisors (724316).

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

523840 is a wasteful number, since it uses less digits than its factorization.

523840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1654 (or 1644 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 523840 is about 723.7679186037. The cubic root of 523840 is about 80.6119733376.

Adding to 523840 its product of nonzero digits (960), we get a triangular number (524800 = T₁₀₂₄).

The spelling of 523840 in words is "five hundred twenty-three thousand, eight hundred forty".