13021121211221 has 2 divisors, whose sum is σ = 13021121211222. Its totient is φ = 13021121211220.

The previous prime is 13021121211199. The next prime is 13021121211331. The reversal of 13021121211221 is 12211212112031.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9124543910596 + 3896577300625 = 3020686^2 + 1973975^2 .

It is a cyclic number.

It is not a de Polignac number, because 13021121211221 - 2²² = 13021117016917 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 13021121211193 and 13021121211202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13021121211421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6510560605610 + 6510560605611.

It is an arithmetic number, because the mean of its divisors is an integer number (6510560605611).

Almost surely, 2^{13021121211221} is an apocalyptic number.

It is an amenable number.

13021121211221 is a deficient number, since it is larger than the sum of its proper divisors (1).

13021121211221 is an equidigital number, since it uses as much as digits as its factorization.

13021121211221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 20.

Adding to 13021121211221 its reverse (12211212112031), we get a palindrome (25232333323252).

The spelling of 13021121211221 in words is "thirteen trillion, twenty-one billion, one hundred twenty-one million, two hundred eleven thousand, two hundred twenty-one".