18106987 has 4 divisors (see below), whose sum is σ = 18118296. Its totient is φ = 18095680.

The previous prime is 18106969. The next prime is 18106997. The reversal of 18106987 is 78960181.

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.

It is a cyclic number.

It is not a de Polignac number, because 18106987 - 2¹¹ = 18104939 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18106997) 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 3 ways as a sum of consecutive naturals, for example, 2758 + ... + 6619.

It is an arithmetic number, because the mean of its divisors is an integer number (4529574).

Almost surely, 2^18106987 is an apocalyptic number.

18106987 is a deficient number, since it is larger than the sum of its proper divisors (11309).

18106987 is an equidigital number, since it uses as much as digits as its factorization.

18106987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11308.

The product of its (nonzero) digits is 24192, while the sum is 40.

The square root of 18106987 is about 4255.2305460457. The cubic root of 18106987 is about 262.5923460430.

The spelling of 18106987 in words is "eighteen million, one hundred six thousand, nine hundred eighty-seven".