18444444 has 12 divisors (see below), whose sum is σ = 43037064. Its totient is φ = 6148144.

The previous prime is 18444427. The next prime is 18444457. The reversal of 18444444 is 44444481.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

18444444 is a modest number, since divided by 4444 gives 1844 as remainder.

It is a congruent number.

It is an unprimeable number.

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, 768507 + ... + 768530.

It is an arithmetic number, because the mean of its divisors is an integer number (3586422).

Almost surely, 2^18444444 is an apocalyptic number.

It is an amenable number.

18444444 is an abundant number, since it is smaller than the sum of its proper divisors (24592620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18444444 is a wasteful number, since it uses less digits than its factorization.

18444444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1537044 (or 1537042 counting only the distinct ones).

The product of its digits is 32768, while the sum is 33.

The square root of 18444444 is about 4294.6995238317. The cubic root of 18444444 is about 264.2136126941.

The spelling of 18444444 in words is "eighteen million, four hundred forty-four thousand, four hundred forty-four".