18044861 has 4 divisors (see below), whose sum is σ = 18085500. Its totient is φ = 18004224.

The previous prime is 18044849. The next prime is 18044869. The reversal of 18044861 is 16844081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16844081 = 227 ⋅74203.

It can be written as a sum of positive squares in 2 ways, for example, as 4280761 + 13764100 = 2069^2 + 3710^2 .

It is a cyclic number.

It is not a de Polignac number, because 18044861 - 2¹⁴ = 18028477 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18044869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19646 + ... + 20543.

It is an arithmetic number, because the mean of its divisors is an integer number (4521375).

Almost surely, 2^18044861 is an apocalyptic number.

It is an amenable number.

18044861 is a deficient number, since it is larger than the sum of its proper divisors (40639).

18044861 is an equidigital number, since it uses as much as digits as its factorization.

18044861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40638.

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 18044861 is about 4247.9243166516. The cubic root of 18044861 is about 262.2916793155.

The spelling of 18044861 in words is "eighteen million, forty-four thousand, eight hundred sixty-one".