1221168901 has 2 divisors, whose sum is σ = 1221168902. Its totient is φ = 1221168900.

The previous prime is 1221168889. The next prime is 1221168929. The reversal of 1221168901 is 1098611221.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1221153025 + 15876 = 34945^2 + 126^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221168901 - 2⁵ = 1221168869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221168401) 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, 610584450 + 610584451.

It is an arithmetic number, because the mean of its divisors is an integer number (610584451).

Almost surely, 2^1221168901 is an apocalyptic number.

It is an amenable number.

1221168901 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221168901 is an equidigital number, since it uses as much as digits as its factorization.

1221168901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 31.

The square root of 1221168901 is about 34945.2271562226. The cubic root of 1221168901 is about 1068.8708795437.

The spelling of 1221168901 in words is "one billion, two hundred twenty-one million, one hundred sixty-eight thousand, nine hundred one".