844189917121 has 2 divisors, whose sum is σ = 844189917122. Its totient is φ = 844189917120.

The previous prime is 844189917119. The next prime is 844189917127. The reversal of 844189917121 is 121719981448.

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., 787576377025 + 56613540096 = 887455^2 + 237936^2 .

It is a cyclic number.

It is not a de Polignac number, because 844189917121 - 2¹ = 844189917119 is a prime.

Together with 844189917119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (844189917127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 422094958560 + 422094958561.

It is an arithmetic number, because the mean of its divisors is an integer number (422094958561).

Almost surely, 2^844189917121 is an apocalyptic number.

It is an amenable number.

844189917121 is a deficient number, since it is larger than the sum of its proper divisors (1).

844189917121 is an equidigital number, since it uses as much as digits as its factorization.

844189917121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1161216, while the sum is 55.

The spelling of 844189917121 in words is "eight hundred forty-four billion, one hundred eighty-nine million, nine hundred seventeen thousand, one hundred twenty-one".