18445549 has 4 divisors (see below), whose sum is σ = 18624736. Its totient is φ = 18266364.

The previous prime is 18445547. The next prime is 18445571. The reversal of 18445549 is 94554481.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18445549 - 2¹ = 18445547 is a prime.

It is a super-2 number, since 2×18445549² = 680476555822802, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18445541) 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, 89439 + ... + 89644.

It is an arithmetic number, because the mean of its divisors is an integer number (4656184).

Almost surely, 2^18445549 is an apocalyptic number.

It is an amenable number.

18445549 is a deficient number, since it is larger than the sum of its proper divisors (179187).

18445549 is a wasteful number, since it uses less digits than its factorization.

18445549 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179186.

The product of its digits is 115200, while the sum is 40.

The square root of 18445549 is about 4294.8281688561. The cubic root of 18445549 is about 264.2188889029.

The spelling of 18445549 in words is "eighteen million, four hundred forty-five thousand, five hundred forty-nine".