18338861 has 4 divisors (see below), whose sum is σ = 18365724. Its totient is φ = 18312000.

The previous prime is 18338833. The next prime is 18338867. The reversal of 18338861 is 16883381.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10465225 + 7873636 = 3235^2 + 2806^2 .

It is a cyclic number.

It is not a de Polignac number, because 18338861 - 2¹⁴ = 18322477 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 (18338867) 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 3 ways as a sum of consecutive naturals, for example, 12380 + ... + 13781.

It is an arithmetic number, because the mean of its divisors is an integer number (4591431).

Almost surely, 2^18338861 is an apocalyptic number.

It is an amenable number.

18338861 is a deficient number, since it is larger than the sum of its proper divisors (26863).

18338861 is an equidigital number, since it uses as much as digits as its factorization.

18338861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26862.

The product of its digits is 27648, while the sum is 38.

The square root of 18338861 is about 4282.3896366398. The cubic root of 18338861 is about 263.7084946256.

The spelling of 18338861 in words is "eighteen million, three hundred thirty-eight thousand, eight hundred sixty-one".