18730009 has 2 divisors, whose sum is σ = 18730010. Its totient is φ = 18730008.

The previous prime is 18730001. The next prime is 18730091. The reversal of 18730009 is 90003781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16160400 + 2569609 = 4020^2 + 1603^2 .

It is a cyclic number.

It is not a de Polignac number, because 18730009 - 2³ = 18730001 is a prime.

It is equal to p_1194922 and since 18730009 and 1194922 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (18730001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9365004 + 9365005.

It is an arithmetic number, because the mean of its divisors is an integer number (9365005).

Almost surely, 2^18730009 is an apocalyptic number.

It is an amenable number.

18730009 is a deficient number, since it is larger than the sum of its proper divisors (1).

18730009 is an equidigital number, since it uses as much as digits as its factorization.

18730009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 18730009 is about 4327.8180414615. The cubic root of 18730009 is about 265.5701926876.

The spelling of 18730009 in words is "eighteen million, seven hundred thirty thousand, nine".