18681289 has 8 divisors (see below), whose sum is σ = 20437920. Its totient is φ = 16934400.

The previous prime is 18681287. The next prime is 18681301. The reversal of 18681289 is 98218681.

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 18681289 - 2¹ = 18681287 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18681287) 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, 1929 + ... + 6409.

It is an arithmetic number, because the mean of its divisors is an integer number (2554740).

Almost surely, 2^18681289 is an apocalyptic number.

It is an amenable number.

18681289 is a deficient number, since it is larger than the sum of its proper divisors (1756631).

18681289 is a wasteful number, since it uses less digits than its factorization.

18681289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4871.

The product of its digits is 55296, while the sum is 43.

The square root of 18681289 is about 4322.1856739386. The cubic root of 18681289 is about 265.3397280444.

The spelling of 18681289 in words is "eighteen million, six hundred eighty-one thousand, two hundred eighty-nine".