531540321 has 24 divisors (see below), whose sum is σ = 771850080. Its totient is φ = 325218816.

The previous prime is 531540319. The next prime is 531540323. The reversal of 531540321 is 123045135.

It is an interprime number because it is at equal distance from previous prime (531540319) and next prime (531540323).

It is not a de Polignac number, because 531540321 - 2¹ = 531540319 is a prime.

It is a super-2 number, since 2×531540321² = 565070225697566082, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 531540291 and 531540300.

It is not an unprimeable number, because it can be changed into a prime (531540323) 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 23 ways as a sum of consecutive naturals, for example, 87825 + ... + 93681.

It is an arithmetic number, because the mean of its divisors is an integer number (32160420).

Almost surely, 2^531540321 is an apocalyptic number.

It is an amenable number.

531540321 is a deficient number, since it is larger than the sum of its proper divisors (240309759).

531540321 is a wasteful number, since it uses less digits than its factorization.

531540321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6065 (or 6052 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 531540321 is about 23055.1582297758. The cubic root of 531540321 is about 810.0504571525.

Adding to 531540321 its reverse (123045135), we get a palindrome (654585456).

The spelling of 531540321 in words is "five hundred thirty-one million, five hundred forty thousand, three hundred twenty-one".