21031210201321 has 2 divisors, whose sum is σ = 21031210201322. Its totient is φ = 21031210201320.

The previous prime is 21031210201303. The next prime is 21031210201357. The reversal of 21031210201321 is 12310201213012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20887057095696 + 144153105625 = 4570236^2 + 379675^2 .

It is a cyclic number.

It is not a de Polignac number, because 21031210201321 - 2⁹ = 21031210200809 is a prime.

It is not a weakly prime, because it can be changed into another prime (21031210211321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515605100660 + 10515605100661.

It is an arithmetic number, because the mean of its divisors is an integer number (10515605100661).

Almost surely, 2^{21031210201321} is an apocalyptic number.

It is an amenable number.

21031210201321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031210201321 is an equidigital number, since it uses as much as digits as its factorization.

21031210201321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 21031210201321 its reverse (12310201213012), we get a palindrome (33341411414333).

The spelling of 21031210201321 in words is "twenty-one trillion, thirty-one billion, two hundred ten million, two hundred one thousand, three hundred twenty-one".