18973549 has 8 divisors (see below), whose sum is σ = 21720320. Its totient is φ = 16235856.

The previous prime is 18973531. The next prime is 18973553. The reversal of 18973549 is 94537981.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18973549 - 2⁵ = 18973517 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18973499 and 18973508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18973589) 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 7 ways as a sum of consecutive naturals, for example, 3052 + ... + 6874.

It is an arithmetic number, because the mean of its divisors is an integer number (2715040).

Almost surely, 2^18973549 is an apocalyptic number.

It is an amenable number.

18973549 is a deficient number, since it is larger than the sum of its proper divisors (2746771).

18973549 is an equidigital number, since it uses as much as digits as its factorization.

18973549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4539.

The product of its digits is 272160, while the sum is 46.

The square root of 18973549 is about 4355.8637490170. The cubic root of 18973549 is about 266.7162794843.

The spelling of 18973549 in words is "eighteen million, nine hundred seventy-three thousand, five hundred forty-nine".