531128420 has 48 divisors (see below), whose sum is σ = 1167965568. Its totient is φ = 202498560.

The previous prime is 531128401. The next prime is 531128431. The reversal of 531128420 is 24821135.

It is a self number, because there is not a number n which added to its sum of digits gives 531128420.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139340 + ... + 143100.

It is an arithmetic number, because the mean of its divisors is an integer number (24332616).

Almost surely, 2^531128420 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 531128420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (583982784).

531128420 is an abundant number, since it is smaller than the sum of its proper divisors (636837148).

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

531128420 is a wasteful number, since it uses less digits than its factorization.

531128420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4100 (or 4098 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 531128420 is about 23046.2235518100. The cubic root of 531128420 is about 809.8411617620.

Adding to 531128420 its reverse (24821135), we get a palindrome (555949555).

The spelling of 531128420 in words is "five hundred thirty-one million, one hundred twenty-eight thousand, four hundred twenty".