531540 has 36 divisors (see below), whose sum is σ = 1612884. Its totient is φ = 141696.

The previous prime is 531521. The next prime is 531547. The reversal of 531540 is 45135.

It can be written as a sum of positive squares in 2 ways, for example, as 318096 + 213444 = 564^2 + 462^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a plaindrome in base 11.

It is a nialpdrome in base 15.

It is a zygodrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (531547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1297 + ... + 1656.

2⁵³¹⁵⁴⁰ is an apocalyptic number.

It is an amenable number.

531540 is an abundant number, since it is smaller than the sum of its proper divisors (1081344).

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

531540 is a wasteful number, since it uses less digits than its factorization.

531540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2968 (or 2963 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

The square root of 531540 is about 729.0678980726. The cubic root of 531540 is about 81.0050294088.

Adding to 531540 its reverse (45135), we get a palindrome (576675).

The spelling of 531540 in words is "five hundred thirty-one thousand, five hundred forty".