1221302213 has 2 divisors, whose sum is σ = 1221302214. Its totient is φ = 1221302212.

The previous prime is 1221302171. The next prime is 1221302227. The reversal of 1221302213 is 3122031221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 959574529 + 261727684 = 30977^2 + 16178^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221302213 - 2⁶ = 1221302149 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1221302191 and 1221302200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221302513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610651106 + 610651107.

It is an arithmetic number, because the mean of its divisors is an integer number (610651107).

Almost surely, 2^1221302213 is an apocalyptic number.

It is an amenable number.

1221302213 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221302213 is an equidigital number, since it uses as much as digits as its factorization.

1221302213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 1221302213 is about 34947.1345463401. The cubic root of 1221302213 is about 1068.9097734618.

Adding to 1221302213 its reverse (3122031221), we get a palindrome (4343333434).

The spelling of 1221302213 in words is "one billion, two hundred twenty-one million, three hundred two thousand, two hundred thirteen".