1321112543221 has 2 divisors, whose sum is σ = 1321112543222. Its totient is φ = 1321112543220.

The previous prime is 1321112543183. The next prime is 1321112543269. The reversal of 1321112543221 is 1223452111231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1039033648900 + 282078894321 = 1019330^2 + 531111^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321112543221 - 2¹⁵ = 1321112510453 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1321112543221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321112543291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660556271610 + 660556271611.

It is an arithmetic number, because the mean of its divisors is an integer number (660556271611).

Almost surely, 2^{1321112543221} is an apocalyptic number.

It is an amenable number.

1321112543221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321112543221 is an equidigital number, since it uses as much as digits as its factorization.

1321112543221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2880, while the sum is 28.

Adding to 1321112543221 its reverse (1223452111231), we get a palindrome (2544564654452).

The spelling of 1321112543221 in words is "one trillion, three hundred twenty-one billion, one hundred twelve million, five hundred forty-three thousand, two hundred twenty-one".