20131303312321 has 2 divisors, whose sum is σ = 20131303312322. Its totient is φ = 20131303312320.

The previous prime is 20131303312319. The next prime is 20131303312327. The reversal of 20131303312321 is 12321330313102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16352633857921 + 3778669454400 = 4043839^2 + 1943880^2 .

It is a cyclic number.

It is not a de Polignac number, because 20131303312321 - 2¹ = 20131303312319 is a prime.

Together with 20131303312319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20131303312327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10065651656160 + 10065651656161.

It is an arithmetic number, because the mean of its divisors is an integer number (10065651656161).

Almost surely, 2^{20131303312321} is an apocalyptic number.

It is an amenable number.

20131303312321 is a deficient number, since it is larger than the sum of its proper divisors (1).

20131303312321 is an equidigital number, since it uses as much as digits as its factorization.

20131303312321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 25.

Adding to 20131303312321 its reverse (12321330313102), we get a palindrome (32452633625423).

The spelling of 20131303312321 in words is "twenty trillion, one hundred thirty-one billion, three hundred three million, three hundred twelve thousand, three hundred twenty-one".