18678997 has 8 divisors (see below), whose sum is σ = 19203200. Its totient is φ = 18162144.

The previous prime is 18678977. The next prime is 18679009. The reversal of 18678997 is 79987681.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18678997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18678917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3529 + ... + 7057.

It is an arithmetic number, because the mean of its divisors is an integer number (2400400).

Almost surely, 2^18678997 is an apocalyptic number.

18678997 is the 3529-th pentagonal number.

It is an amenable number.

18678997 is a deficient number, since it is larger than the sum of its proper divisors (524203).

18678997 is an equidigital number, since it uses as much as digits as its factorization.

18678997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3675.

The product of its digits is 1524096, while the sum is 55.

The square root of 18678997 is about 4321.9205221753. The cubic root of 18678997 is about 265.3288761249.

The spelling of 18678997 in words is "eighteen million, six hundred seventy-eight thousand, nine hundred ninety-seven".