185131109 has 2 divisors, whose sum is σ = 185131110. Its totient is φ = 185131108.

The previous prime is 185131061. The next prime is 185131127. The reversal of 185131109 is 901131581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155700484 + 29430625 = 12478^2 + 5425^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-185131109 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (185131169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 92565554 + 92565555.

It is an arithmetic number, because the mean of its divisors is an integer number (92565555).

Almost surely, 2^185131109 is an apocalyptic number.

It is an amenable number.

185131109 is a deficient number, since it is larger than the sum of its proper divisors (1).

185131109 is an equidigital number, since it uses as much as digits as its factorization.

185131109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 29.

The square root of 185131109 is about 13606.2893178118. The cubic root of 185131109 is about 569.9364954387.

The spelling of 185131109 in words is "one hundred eighty-five million, one hundred thirty-one thousand, one hundred nine".