18548549209 has 2 divisors, whose sum is σ = 18548549210. Its totient is φ = 18548549208.

The previous prime is 18548549191. The next prime is 18548549213. The reversal of 18548549209 is 90294584581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11836352025 + 6712197184 = 108795^2 + 81928^2 .

It is a cyclic number.

It is not a de Polignac number, because 18548549209 - 2¹⁹ = 18548024921 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18548549209.

It is not a weakly prime, because it can be changed into another prime (18548540209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9274274604 + 9274274605.

It is an arithmetic number, because the mean of its divisors is an integer number (9274274605).

Almost surely, 2^18548549209 is an apocalyptic number.

It is an amenable number.

18548549209 is a deficient number, since it is larger than the sum of its proper divisors (1).

18548549209 is an equidigital number, since it uses as much as digits as its factorization.

18548549209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4147200, while the sum is 55.

The spelling of 18548549209 in words is "eighteen billion, five hundred forty-eight million, five hundred forty-nine thousand, two hundred nine".