18438673 has 4 divisors (see below), whose sum is σ = 20114928. Its totient is φ = 16762420.

The previous prime is 18438649. The next prime is 18438689. The reversal of 18438673 is 37683481.

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 18438673 - 2¹³ = 18430481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18438613) 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, 838111 + ... + 838132.

It is an arithmetic number, because the mean of its divisors is an integer number (5028732).

Almost surely, 2^18438673 is an apocalyptic number.

It is an amenable number.

18438673 is a deficient number, since it is larger than the sum of its proper divisors (1676255).

18438673 is a wasteful number, since it uses less digits than its factorization.

18438673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1676254.

The product of its digits is 96768, while the sum is 40.

The square root of 18438673 is about 4294.0275965578. The cubic root of 18438673 is about 264.1860536125.

The spelling of 18438673 in words is "eighteen million, four hundred thirty-eight thousand, six hundred seventy-three".