1212212193809 has 2 divisors, whose sum is σ = 1212212193810. Its totient is φ = 1212212193808.

The previous prime is 1212212193791. The next prime is 1212212193811. The reversal of 1212212193809 is 9083912122121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1105711134784 + 106501059025 = 1051528^2 + 326345^2 .

It is an emirp because it is prime and its reverse (9083912122121) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1212212193809 is a prime.

Together with 1212212193811, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1212212190809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606106096904 + 606106096905.

It is an arithmetic number, because the mean of its divisors is an integer number (606106096905).

Almost surely, 2^{1212212193809} is an apocalyptic number.

It is an amenable number.

1212212193809 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212212193809 is an equidigital number, since it uses as much as digits as its factorization.

1212212193809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 41.

The spelling of 1212212193809 in words is "one trillion, two hundred twelve billion, two hundred twelve million, one hundred ninety-three thousand, eight hundred nine".