18106909 has 2 divisors, whose sum is σ = 18106910. Its totient is φ = 18106908.

The previous prime is 18106903. The next prime is 18106939. The reversal of 18106909 is 90960181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15578809 + 2528100 = 3947^2 + 1590^2 .

It is a cyclic number.

It is not a de Polignac number, because 18106909 - 2³ = 18106901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18106901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9053454 + 9053455.

It is an arithmetic number, because the mean of its divisors is an integer number (9053455).

Almost surely, 2^18106909 is an apocalyptic number.

It is an amenable number.

18106909 is a deficient number, since it is larger than the sum of its proper divisors (1).

18106909 is an equidigital number, since it uses as much as digits as its factorization.

18106909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 18106909 is about 4255.2213808449. The cubic root of 18106909 is about 262.5919689835.

The spelling of 18106909 in words is "eighteen million, one hundred six thousand, nine hundred nine".