1221033121013 has 2 divisors, whose sum is σ = 1221033121014. Its totient is φ = 1221033121012.

The previous prime is 1221033121003. The next prime is 1221033121037. The reversal of 1221033121013 is 3101213301221.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1125960798769 + 95072322244 = 1061113^2 + 308338^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221033121013 - 2¹² = 1221033116917 is a prime.

It is a super-2 number, since 2×1221033121013² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221033121003) 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, 610516560506 + 610516560507.

It is an arithmetic number, because the mean of its divisors is an integer number (610516560507).

Almost surely, 2^{1221033121013} is an apocalyptic number.

It is an amenable number.

1221033121013 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221033121013 is an equidigital number, since it uses as much as digits as its factorization.

1221033121013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 1221033121013 its reverse (3101213301221), we get a palindrome (4322246422234).

The spelling of 1221033121013 in words is "one trillion, two hundred twenty-one billion, thirty-three million, one hundred twenty-one thousand, thirteen".