18105449 has 4 divisors (see below), whose sum is σ = 18128964. Its totient is φ = 18081936.

The previous prime is 18105433. The next prime is 18105467. The reversal of 18105449 is 94450181.

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 7425625 + 10679824 = 2725^2 + 3268^2 .

It is a cyclic number.

It is not a de Polignac number, because 18105449 - 2⁴ = 18105433 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (18105049) 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, 10562 + ... + 12155.

It is an arithmetic number, because the mean of its divisors is an integer number (4532241).

Almost surely, 2^18105449 is an apocalyptic number.

It is an amenable number.

18105449 is a deficient number, since it is larger than the sum of its proper divisors (23515).

18105449 is an equidigital number, since it uses as much as digits as its factorization.

18105449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23514.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 18105449 is about 4255.0498234451. The cubic root of 18105449 is about 262.5849110040.

The spelling of 18105449 in words is "eighteen million, one hundred five thousand, four hundred forty-nine".