8154187109 has 2 divisors, whose sum is σ = 8154187110. Its totient is φ = 8154187108.

The previous prime is 8154187103. The next prime is 8154187123. The reversal of 8154187109 is 9017814518.

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., 4764036484 + 3390150625 = 69022^2 + 58225^2 .

It is a cyclic number.

It is not a de Polignac number, because 8154187109 - 2²⁰ = 8153138533 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 8154187109.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8154187103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4077093554 + 4077093555.

It is an arithmetic number, because the mean of its divisors is an integer number (4077093555).

Almost surely, 2^8154187109 is an apocalyptic number.

It is an amenable number.

8154187109 is a deficient number, since it is larger than the sum of its proper divisors (1).

8154187109 is an equidigital number, since it uses as much as digits as its factorization.

8154187109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 80640, while the sum is 44.

The square root of 8154187109 is about 90300.5377005032. The cubic root of 8154187109 is about 2012.7672509766.

The spelling of 8154187109 in words is "eight billion, one hundred fifty-four million, one hundred eighty-seven thousand, one hundred nine".