18861686 has 4 divisors (see below), whose sum is σ = 28292532. Its totient is φ = 9430842.

The previous prime is 18861683. The next prime is 18861707. The reversal of 18861686 is 68616881.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18861683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4715420 + ... + 4715423.

It is an arithmetic number, because the mean of its divisors is an integer number (7073133).

Almost surely, 2^18861686 is an apocalyptic number.

18861686 is a deficient number, since it is larger than the sum of its proper divisors (9430846).

18861686 is an equidigital number, since it uses as much as digits as its factorization.

18861686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9430845.

The product of its digits is 110592, while the sum is 44.

The square root of 18861686 is about 4343.0042597262. The cubic root of 18861686 is about 266.1910832335.

The spelling of 18861686 in words is "eighteen million, eight hundred sixty-one thousand, six hundred eighty-six".