18009441 has 6 divisors (see below), whose sum is σ = 26013650. Its totient is φ = 12006288.

The previous prime is 18009421. The next prime is 18009461. The reversal of 18009441 is 14490081.

It is an interprime number because it is at equal distance from previous prime (18009421) and next prime (18009461).

It can be written as a sum of positive squares in only one way, i.e., 14288400 + 3721041 = 3780^2 + 1929^2 .

It is not a de Polignac number, because 18009441 - 2¹⁷ = 17878369 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18009401) 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 5 ways as a sum of consecutive naturals, for example, 1000516 + ... + 1000533.

Almost surely, 2^18009441 is an apocalyptic number.

It is an amenable number.

18009441 is a deficient number, since it is larger than the sum of its proper divisors (8004209).

18009441 is a wasteful number, since it uses less digits than its factorization.

18009441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2001055 (or 2001052 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 18009441 is about 4243.7531737838. The cubic root of 18009441 is about 262.1199507079.

The spelling of 18009441 in words is "eighteen million, nine thousand, four hundred forty-one".