18993347 has 4 divisors (see below), whose sum is σ = 19648320. Its totient is φ = 18338376.

The previous prime is 18993343. The next prime is 18993367. The reversal of 18993347 is 74339981.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18993347 - 2² = 18993343 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18993298 and 18993307.

It is not an unprimeable number, because it can be changed into a prime (18993341) 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, 327443 + ... + 327500.

It is an arithmetic number, because the mean of its divisors is an integer number (4912080).

Almost surely, 2^18993347 is an apocalyptic number.

18993347 is a deficient number, since it is larger than the sum of its proper divisors (654973).

18993347 is an equidigital number, since it uses as much as digits as its factorization.

18993347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 654972.

The product of its digits is 163296, while the sum is 44.

The square root of 18993347 is about 4358.1357252844. The cubic root of 18993347 is about 266.8090158394.

The spelling of 18993347 in words is "eighteen million, nine hundred ninety-three thousand, three hundred forty-seven".