1221123361 has 2 divisors, whose sum is σ = 1221123362. Its totient is φ = 1221123360.

The previous prime is 1221123349. The next prime is 1221123367. The reversal of 1221123361 is 1633211221.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1001342736 + 219780625 = 31644^2 + 14825^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221123361 - 2⁹ = 1221122849 is a prime.

It is a super-2 number, since 2×1221123361² = 2982284525559872642, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1221123367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610561680 + 610561681.

It is an arithmetic number, because the mean of its divisors is an integer number (610561681).

Almost surely, 2^1221123361 is an apocalyptic number.

It is an amenable number.

1221123361 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221123361 is an equidigital number, since it uses as much as digits as its factorization.

1221123361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 22.

The square root of 1221123361 is about 34944.5755590192. The cubic root of 1221123361 is about 1068.8575925515.

Adding to 1221123361 its reverse (1633211221), we get a palindrome (2854334582).

The spelling of 1221123361 in words is "one billion, two hundred twenty-one million, one hundred twenty-three thousand, three hundred sixty-one".