18712009 has 8 divisors (see below), whose sum is σ = 19321632. Its totient is φ = 18110400.

The previous prime is 18712007. The next prime is 18712013. The reversal of 18712009 is 90021781.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18712009 - 2¹ = 18712007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18712007) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2934 + ... + 6784.

It is an arithmetic number, because the mean of its divisors is an integer number (2415204).

Almost surely, 2^18712009 is an apocalyptic number.

It is an amenable number.

18712009 is a deficient number, since it is larger than the sum of its proper divisors (609623).

18712009 is a wasteful number, since it uses less digits than its factorization.

18712009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4007.

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

The square root of 18712009 is about 4325.7379717223. The cubic root of 18712009 is about 265.4850922550.

The spelling of 18712009 in words is "eighteen million, seven hundred twelve thousand, nine".