18609449 has 4 divisors (see below), whose sum is σ = 19063380. Its totient is φ = 18155520.

The previous prime is 18609443. The next prime is 18609457. The reversal of 18609449 is 94490681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94490681 = 137 ⋅689713.

It can be written as a sum of positive squares in 2 ways, for example, as 8369449 + 10240000 = 2893^2 + 3200^2 .

It is a cyclic number.

It is not a de Polignac number, because 18609449 - 2⁴ = 18609433 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41), and also a Moran number because the ratio is a prime number: 453889 = 18609449 / (1 + 8 + 6 + 0 + 9 + 4 + 4 + 9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18609443) 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, 226904 + ... + 226985.

It is an arithmetic number, because the mean of its divisors is an integer number (4765845).

Almost surely, 2^18609449 is an apocalyptic number.

It is an amenable number.

18609449 is a deficient number, since it is larger than the sum of its proper divisors (453931).

18609449 is an equidigital number, since it uses as much as digits as its factorization.

18609449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453930.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 18609449 is about 4313.8670586841. The cubic root of 18609449 is about 264.9991645874. Note that the first 3 decimals are identical.

The spelling of 18609449 in words is "eighteen million, six hundred nine thousand, four hundred forty-nine".