18986851 has 8 divisors (see below), whose sum is σ = 21152880. Its totient is φ = 16921632.

The previous prime is 18986839. The next prime is 18986857. The reversal of 18986851 is 15868981.

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

It is a de Polignac number, because none of the positive numbers 2^k-18986851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18986857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24805 + ... + 25558.

It is an arithmetic number, because the mean of its divisors is an integer number (2644110).

Almost surely, 2^18986851 is an apocalyptic number.

18986851 is a deficient number, since it is larger than the sum of its proper divisors (2166029).

18986851 is a wasteful number, since it uses less digits than its factorization.

18986851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50405.

The product of its digits is 138240, while the sum is 46.

The square root of 18986851 is about 4357.3903887533. The cubic root of 18986851 is about 266.7785948540.

The spelling of 18986851 in words is "eighteen million, nine hundred eighty-six thousand, eight hundred fifty-one".