1213420353221 has 2 divisors, whose sum is σ = 1213420353222. Its totient is φ = 1213420353220.

The previous prime is 1213420353193. The next prime is 1213420353259. The reversal of 1213420353221 is 1223530243121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1206128901121 + 7291452100 = 1098239^2 + 85390^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213420353221 - 2³⁰ = 1212346611397 is a prime.

It is a super-2 number, since 2×1213420353221² (a number of 25 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1213420353121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606710176610 + 606710176611.

It is an arithmetic number, because the mean of its divisors is an integer number (606710176611).

Almost surely, 2^{1213420353221} is an apocalyptic number.

It is an amenable number.

1213420353221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213420353221 is an equidigital number, since it uses as much as digits as its factorization.

1213420353221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 29.

Adding to 1213420353221 its reverse (1223530243121), we get a palindrome (2436950596342).

The spelling of 1213420353221 in words is "one trillion, two hundred thirteen billion, four hundred twenty million, three hundred fifty-three thousand, two hundred twenty-one".