18207109 has 2 divisors, whose sum is σ = 18207110. Its totient is φ = 18207108.

The previous prime is 18207089. The next prime is 18207131. The reversal of 18207109 is 90170281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16176484 + 2030625 = 4022^2 + 1425^2 .

It is a cyclic number.

It is not a de Polignac number, because 18207109 - 2¹⁵ = 18174341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18207179) 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, 9103554 + 9103555.

It is an arithmetic number, because the mean of its divisors is an integer number (9103555).

Almost surely, 2^18207109 is an apocalyptic number.

It is an amenable number.

18207109 is a deficient number, since it is larger than the sum of its proper divisors (1).

18207109 is an equidigital number, since it uses as much as digits as its factorization.

18207109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 18207109 is about 4266.9789078457. The cubic root of 18207109 is about 263.0754553215.

The spelling of 18207109 in words is "eighteen million, two hundred seven thousand, one hundred nine".