18351866 has 8 divisors (see below), whose sum is σ = 29645364. Its totient is φ = 8470080.

The previous prime is 18351859. The next prime is 18351869. The reversal of 18351866 is 66815381.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18309841 + 42025 = 4279^2 + 205^2 .

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

It is not an unprimeable number, because it can be changed into a prime (18351869) 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, 352895 + ... + 352946.

Almost surely, 2^18351866 is an apocalyptic number.

18351866 is a deficient number, since it is larger than the sum of its proper divisors (11293498).

18351866 is a wasteful number, since it uses less digits than its factorization.

18351866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 705856.

The product of its digits is 34560, while the sum is 38.

The square root of 18351866 is about 4283.9077954597. The cubic root of 18351866 is about 263.7708161734.

The spelling of 18351866 in words is "eighteen million, three hundred fifty-one thousand, eight hundred sixty-six".