13121333221 has 2 divisors, whose sum is σ = 13121333222. Its totient is φ = 13121333220.

The previous prime is 13121333207. The next prime is 13121333233. The reversal of 13121333221 is 12233312131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8374812196 + 4746521025 = 91514^2 + 68895^2 .

It is a cyclic number.

It is not a de Polignac number, because 13121333221 - 2¹⁵ = 13121300453 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 13121333192 and 13121333201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13121333321) 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, 6560666610 + 6560666611.

It is an arithmetic number, because the mean of its divisors is an integer number (6560666611).

Almost surely, 2^13121333221 is an apocalyptic number.

It is an amenable number.

13121333221 is a deficient number, since it is larger than the sum of its proper divisors (1).

13121333221 is an equidigital number, since it uses as much as digits as its factorization.

13121333221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 22.

Adding to 13121333221 its reverse (12233312131), we get a palindrome (25354645352).

The spelling of 13121333221 in words is "thirteen billion, one hundred twenty-one million, three hundred thirty-three thousand, two hundred twenty-one".