531840 has 64 divisors (see below), whose sum is σ = 1701360. Its totient is φ = 141312.

The previous prime is 531833. The next prime is 531841. The reversal of 531840 is 48135.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 531840.

It is not an unprimeable number, because it can be changed into a prime (531841) by changing a digit.

531840 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, 1782 + ... + 2058.

2⁵³¹⁸⁴⁰ 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 531840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (850680).

531840 is an abundant number, since it is smaller than the sum of its proper divisors (1169520).

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

531840 is a wasteful number, since it uses less digits than its factorization.

531840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299 (or 287 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 531840 is about 729.2736112050. The cubic root of 531840 is about 81.0202662291.

Adding to 531840 its reverse (48135), we get a palindrome (579975).

It can be divided in two parts, 531 and 840, that multiplied together give a triangular number (446040 = T₉₄₄).

The spelling of 531840 in words is "five hundred thirty-one thousand, eight hundred forty".