78961105189 has 2 divisors, whose sum is σ = 78961105190. Its totient is φ = 78961105188.

The previous prime is 78961105187. The next prime is 78961105207. The reversal of 78961105189 is 98150116987.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74586341025 + 4374764164 = 273105^2 + 66142^2 .

It is a cyclic number.

It is not a de Polignac number, because 78961105189 - 2¹ = 78961105187 is a prime.

It is a super-3 number, since 3×78961105189³ (a number of 34 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 78961105187, 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 (78961105187) 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, 39480552594 + 39480552595.

It is an arithmetic number, because the mean of its divisors is an integer number (39480552595).

Almost surely, 2^78961105189 is an apocalyptic number.

It is an amenable number.

78961105189 is a deficient number, since it is larger than the sum of its proper divisors (1).

78961105189 is an equidigital number, since it uses as much as digits as its factorization.

78961105189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1088640, while the sum is 55.

The spelling of 78961105189 in words is "seventy-eight billion, nine hundred sixty-one million, one hundred five thousand, one hundred eighty-nine".