121660255789 has 2 divisors, whose sum is σ = 121660255790. Its totient is φ = 121660255788.

The previous prime is 121660255741. The next prime is 121660255793. The reversal of 121660255789 is 987552066121.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 106664294025 + 14995961764 = 326595^2 + 122458^2 .

It is an emirp because it is prime and its reverse (987552066121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121660255789 - 2¹⁵ = 121660223021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121660255709) 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, 60830127894 + 60830127895.

It is an arithmetic number, because the mean of its divisors is an integer number (60830127895).

Almost surely, 2^121660255789 is an apocalyptic number.

It is an amenable number.

121660255789 is a deficient number, since it is larger than the sum of its proper divisors (1).

121660255789 is an equidigital number, since it uses as much as digits as its factorization.

121660255789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1814400, while the sum is 52.

The spelling of 121660255789 in words is "one hundred twenty-one billion, six hundred sixty million, two hundred fifty-five thousand, seven hundred eighty-nine".