1221241404109 has 2 divisors, whose sum is σ = 1221241404110. Its totient is φ = 1221241404108.

The previous prime is 1221241404017. The next prime is 1221241404157. The reversal of 1221241404109 is 9014041421221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 742027188100 + 479214216009 = 861410^2 + 692253^2 .

It is an emirp because it is prime and its reverse (9014041421221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221241404109 - 2¹⁵ = 1221241371341 is a prime.

It is a super-2 number, since 2×1221241404109² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221241404199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610620702054 + 610620702055.

It is an arithmetic number, because the mean of its divisors is an integer number (610620702055).

Almost surely, 2^{1221241404109} is an apocalyptic number.

It is an amenable number.

1221241404109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221241404109 is an equidigital number, since it uses as much as digits as its factorization.

1221241404109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 31.

The spelling of 1221241404109 in words is "one trillion, two hundred twenty-one billion, two hundred forty-one million, four hundred four thousand, one hundred nine".