531132321 has 4 divisors (see below), whose sum is σ = 708176432. Its totient is φ = 354088212.

The previous prime is 531132319. The next prime is 531132341. The reversal of 531132321 is 123231135.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 531132321 - 2¹ = 531132319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (531132341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88522051 + ... + 88522056.

It is an arithmetic number, because the mean of its divisors is an integer number (177044108).

Almost surely, 2^531132321 is an apocalyptic number.

It is an amenable number.

531132321 is a deficient number, since it is larger than the sum of its proper divisors (177044111).

531132321 is a wasteful number, since it uses less digits than its factorization.

531132321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177044110.

The product of its digits is 540, while the sum is 21.

The square root of 531132321 is about 23046.3081859113. The cubic root of 531132321 is about 809.8431444480.

Adding to 531132321 its reverse (123231135), we get a palindrome (654363456).

The spelling of 531132321 in words is "five hundred thirty-one million, one hundred thirty-two thousand, three hundred twenty-one".