531321321505 has 24 divisors (see below), whose sum is σ = 690586744248. Its totient is φ = 392256124416.

The previous prime is 531321321473. The next prime is 531321321527. The reversal of 531321321505 is 505123123135.

It can be written as a sum of positive squares in 12 ways, for example, as 18281473681 + 513039847824 = 135209^2 + 716268^2 .

It is not a de Polignac number, because 531321321505 - 2⁵ = 531321321473 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3174189 + ... + 3337381.

It is an arithmetic number, because the mean of its divisors is an integer number (28774447677).

Almost surely, 2^531321321505 is an apocalyptic number.

It is an amenable number.

531321321505 is a deficient number, since it is larger than the sum of its proper divisors (159265422743).

531321321505 is a wasteful number, since it uses less digits than its factorization.

531321321505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167077 (or 167064 counting only the distinct ones).

The product of its (nonzero) digits is 13500, while the sum is 31.

The spelling of 531321321505 in words is "five hundred thirty-one billion, three hundred twenty-one million, three hundred twenty-one thousand, five hundred five".