1221200001097 has 2 divisors, whose sum is σ = 1221200001098. Its totient is φ = 1221200001096.

The previous prime is 1221200001079. The next prime is 1221200001127. The reversal of 1221200001097 is 7901000021221.

Together with previous prime (1221200001079) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1085797344256 + 135402656841 = 1042016^2 + 367971^2 .

It is an emirp because it is prime and its reverse (7901000021221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221200001097 - 2³⁹ = 671444187209 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221200001397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610600000548 + 610600000549.

It is an arithmetic number, because the mean of its divisors is an integer number (610600000549).

Almost surely, 2^{1221200001097} is an apocalyptic number.

It is an amenable number.

1221200001097 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221200001097 is an equidigital number, since it uses as much as digits as its factorization.

1221200001097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 25.

The spelling of 1221200001097 in words is "one trillion, two hundred twenty-one billion, two hundred million, one thousand, ninety-seven".