18310009 has 4 divisors (see below), whose sum is σ = 18319204. Its totient is φ = 18300816.

The previous prime is 18310007. The next prime is 18310013. The reversal of 18310009 is 90001381.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 90001381 = 47 ⋅1914923.

It can be written as a sum of positive squares in 2 ways, for example, as 18147600 + 162409 = 4260^2 + 403^2 .

It is a cyclic number.

It is not a de Polignac number, because 18310009 - 2¹ = 18310007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18310007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 222 + ... + 6055.

It is an arithmetic number, because the mean of its divisors is an integer number (4579801).

Almost surely, 2^18310009 is an apocalyptic number.

It is an amenable number.

18310009 is a deficient number, since it is larger than the sum of its proper divisors (9195).

18310009 is an equidigital number, since it uses as much as digits as its factorization.

18310009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9194.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 18310009 is about 4279.0196307098. The cubic root of 18310009 is about 263.5701270525.

The spelling of 18310009 in words is "eighteen million, three hundred ten thousand, nine".