18916249 has 4 divisors (see below), whose sum is σ = 20635920. Its totient is φ = 17196580.

The previous prime is 18916243. The next prime is 18916253. The reversal of 18916249 is 94261981.

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 18916249 - 2³ = 18916241 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18916241) 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, 859819 + ... + 859840.

It is an arithmetic number, because the mean of its divisors is an integer number (5158980).

Almost surely, 2^18916249 is an apocalyptic number.

It is an amenable number.

18916249 is a deficient number, since it is larger than the sum of its proper divisors (1719671).

18916249 is a wasteful number, since it uses less digits than its factorization.

18916249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1719670.

The product of its digits is 31104, while the sum is 40.

The square root of 18916249 is about 4349.2814349039. The cubic root of 18916249 is about 266.4475149115.

The spelling of 18916249 in words is "eighteen million, nine hundred sixteen thousand, two hundred forty-nine".