20321331253537 has 2 divisors, whose sum is σ = 20321331253538. Its totient is φ = 20321331253536.

The previous prime is 20321331253529. The next prime is 20321331253541. The reversal of 20321331253537 is 73535213312302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18280421864721 + 2040909388816 = 4275561^2 + 1428604^2 .

It is a cyclic number.

It is not a de Polignac number, because 20321331253537 - 2³ = 20321331253529 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20321331253537.

It is not a weakly prime, because it can be changed into another prime (20321331253507) by changing a digit.

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 as a sum of consecutive naturals, namely, 10160665626768 + 10160665626769.

It is an arithmetic number, because the mean of its divisors is an integer number (10160665626769).

Almost surely, 2^{20321331253537} is an apocalyptic number.

It is an amenable number.

20321331253537 is a deficient number, since it is larger than the sum of its proper divisors (1).

20321331253537 is an equidigital number, since it uses as much as digits as its factorization.

20321331253537 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 340200, while the sum is 40.

Adding to 20321331253537 its reverse (73535213312302), we get a palindrome (93856544565839).

The spelling of 20321331253537 in words is "twenty trillion, three hundred twenty-one billion, three hundred thirty-one million, two hundred fifty-three thousand, five hundred thirty-seven".