531720 has 96 divisors (see below), whose sum is σ = 1984320. Its totient is φ = 120960.

The previous prime is 531701. The next prime is 531731. The reversal of 531720 is 27135.

It is a super-3 number, since 3×531720³ = 450993458833344000, which contains 333 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 531693 and 531702.

It is an unprimeable number.

531720 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 23 ways as a sum of consecutive naturals, for example, 2415 + ... + 2625.

It is an arithmetic number, because the mean of its divisors is an integer number (20670).

2⁵³¹⁷²⁰ 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 531720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (992160).

531720 is an abundant number, since it is smaller than the sum of its proper divisors (1452600).

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

531720 is a wasteful number, since it uses less digits than its factorization.

531720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235 (or 228 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 18.

The square root of 531720 is about 729.1913329161. The cubic root of 531720 is about 81.0141721887.

Adding to 531720 its reverse (27135), we get a palindrome (558855).

The spelling of 531720 in words is "five hundred thirty-one thousand, seven hundred twenty".