1236194421109 has 2 divisors, whose sum is σ = 1236194421110. Its totient is φ = 1236194421108.

The previous prime is 1236194421107. The next prime is 1236194421127. The reversal of 1236194421109 is 9011244916321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1166231526084 + 69962895025 = 1079922^2 + 264505^2 .

It is an emirp because it is prime and its reverse (9011244916321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1236194421109 - 2¹ = 1236194421107 is a prime.

Together with 1236194421107, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1236194421107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 618097210554 + 618097210555.

It is an arithmetic number, because the mean of its divisors is an integer number (618097210555).

Almost surely, 2^{1236194421109} is an apocalyptic number.

It is an amenable number.

1236194421109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1236194421109 is an equidigital number, since it uses as much as digits as its factorization.

1236194421109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312, while the sum is 43.

The spelling of 1236194421109 in words is "one trillion, two hundred thirty-six billion, one hundred ninety-four million, four hundred twenty-one thousand, one hundred nine".