18984993 has 4 divisors (see below), whose sum is σ = 25313328. Its totient is φ = 12656660.

The previous prime is 18984991. The next prime is 18985003. The reversal of 18984993 is 39948981.

It is a happy number.

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 18984993 - 2¹ = 18984991 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18984991) 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, 3164163 + ... + 3164168.

It is an arithmetic number, because the mean of its divisors is an integer number (6328332).

Almost surely, 2^18984993 is an apocalyptic number.

It is an amenable number.

18984993 is a deficient number, since it is larger than the sum of its proper divisors (6328335).

18984993 is an equidigital number, since it uses as much as digits as its factorization.

18984993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6328334.

The product of its digits is 559872, while the sum is 51.

The square root of 18984993 is about 4357.1771825346. The cubic root of 18984993 is about 266.7698925017.

The spelling of 18984993 in words is "eighteen million, nine hundred eighty-four thousand, nine hundred ninety-three".